On 8/26/19 1:46 PM, Marek Polacek wrote:
On Fri, Aug 23, 2019 at 07:39:57PM -0400, Marek Polacek wrote:
On Fri, Aug 23, 2019 at 02:43:42PM -0700, Jason Merrill wrote:
On 8/23/19 9:32 AM, Marek Polacek wrote:
This patch implements another C++20 feature, partially deprecating volatile.
You can read the proposal here: <http://wg21.link/p1152r4>. I encourage
interested people to read the background in <http://wg21.link/p1152r0> which
provides a lot of interesting volatile-related information.
Note that P1152R4 differs slightly from what's now in the standard: the mention
of "non-class type" was dropped. (Assignment to objects of a class type is
defined by the copy/move assignment operator.)
The gist is that expressions that involve both load and store of a volatile
lvalue, such as ++ or += are deprecated, as are volatile-qualified parameter
and return types. Chained assignments of the form "a = b = c" are also
deprecated because there's some confusion as to if 'b' is re-read before storing
the value to 'a' (GCC claims not to do it). See Annex D [depr.volatile.type].
[expr.ass] further says that "A simple assignment whose left operand is of
a volatile-qualified type is deprecated unless the assignment is either
a discarded-value expression or appears in an unevaluated context."
and therein lies the rub. When parsing/building the MODIFY_EXPR, we don't know
if the assignment's value is going to be discared. We only know that after
mark_discarded_use has run, which for expression-statements takes place in
finish_expr_stmt -> conver_to_void, and that is quite late.
It wouldn't work to warn in mark_[lr]value_use?
My worry is that we might be calling those too often and generate redundant
diagnostics but I'll have to play with that a bit before I can say for sure.
So indeed we call mark_use multiple times on the same expr, but that is not an
unsurmountable problem, I just need to use TREE_THIS_VOLATILE to prevent that.
FWIW, using TREE_NO_WARNING didn't work for
&(vi = i);
because finish_parenthesized_expr sets TREE_NO_WARNING and so we wouldn't warn
at all. But warning in mark_use did simplify things a bit, thanks for the
suggestion.
One nit is that we emit two warnings for
vi = vi += 10;
which could be fixed but I'm not entirely sure it's even worth it.
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2019-08-26 Marek Polacek <pola...@redhat.com>
Implement P1152R4: Deprecating some uses of volatile.
PR c++/91361
* c-opts.c (c_common_post_options): Enable -Wvolatile by
default for C++2a, unless -Wno-deprecated.
* c.opt (Wvolatile): New warning.
* cp-gimplify.c (cp_fold): Set TREE_THIS_VOLATILE.
* decl.c (grokdeclarator): Warn about a volatile-qualified structured
binding and return type.
(grokparms): Warn about a volatile-qualified function parameter.
* expr.c (mark_use) <case MODIFY_EXPR>: Emit a -Wvolatile warning.
* typeck.c (cp_build_unary_op): Emit a -Wvolatile warning for pre and
post ++/-- on a volatile operand.
(genericize_compound_lvalue): Use a better location. Don't lose
TREE_THIS_VOLATILE.
(cp_build_modify_expr): Emit a -Wvolatile warning for a compound
assignment whose LHS is volatile-qualified. Build the assignment with
a more precise location.
* doc/invoke.texi: Document -Wvolatile.
* c-c++-common/Wbool-operation-1.c: Use -Wno-volatile in C++.
* c-c++-common/gomp/atomic-1.c: Likewise.
* c-c++-common/gomp/atomic-9.c: Likewise.
* c-c++-common/gomp/depend-iterator-1.c: Likewise.
* c-c++-common/gomp/loop-1.c: Adjust warning location for C++.
* c-c++-common/gomp/order-3.c: Likewise.
* c-c++-common/pr69733.c: Use -Wno-volatile in C++.
* c-c++-common/spec-barrier-2.c: Likewise.
* c-c++-common/tm/pr54893.c: Likewise.
* g++.dg/cpp0x/pr65327.C: Add dg-warning.
* g++.dg/cpp0x/rv-conv2.C: Likewise.
* g++.dg/cpp0x/rv1n.C: Likewise.
* g++.dg/cpp0x/rv1p.C: Likewise.
* g++.dg/cpp0x/rv2n.C: Likewise.
* g++.dg/cpp0x/rv2p.C: Likewise.
* g++.dg/cpp0x/rv3n.C: Likewise.
* g++.dg/cpp0x/rv3p.C: Likewise.
* g++.dg/cpp0x/rv4n.C: Likewise.
* g++.dg/cpp0x/rv4p.C: Likewise.
* g++.dg/cpp0x/rv5n.C: Likewise.
* g++.dg/cpp0x/rv5p.C: Likewise.
* g++.dg/cpp0x/rv6n.C: Likewise.
* g++.dg/cpp0x/rv6p.C: Likewise.
* g++.dg/cpp0x/rv7n.C: Likewise.
* g++.dg/cpp0x/rv7p.C: Likewise.
* g++.dg/cpp0x/rv8p.C: Likewise.
* g++.dg/cpp0x/trailing14.C: Use -Wno-volatile.
* g++.dg/cpp1y/new1.C: Add dg-warning.
* g++.dg/cpp2a/volatile1.C: New test.
* g++.dg/cpp2a/volatile2.C: New test.
* g++.dg/cpp2a/volatile3.C: New test.
* g++.dg/cpp2a/volatile4.C: New test.
* g++.dg/expr/bool3.C: Add dg-warning.
* g++.dg/expr/bool4.C: Likewise.
* g++.dg/expr/cond9.C: Likewise.
* g++.dg/ext/vector25.C: Likewise.
* g++.dg/gomp/depend-iterator-1.C: Use -Wno-volatile.
* g++.dg/inherit/covariant21.C: Add dg-warning.
* g++.dg/init/ref18.C: Likewise.
* g++.dg/ipa/pr63838.C: Likewise.
* g++.dg/overload/rvalue2.C: Likewise.
* g++.dg/parse/semicolon4.C: Likewise.
* g++.dg/warn/Wreturn-type-4.C: Likewise.
* g++.dg/warn/pr36069.C: Likewise.
* g++.old-deja/g++.mike/p9506.C: Likewise.
* g++.old-deja/g++.other/volatile1.C: Likewise.
diff --git gcc/c-family/c-opts.c gcc/c-family/c-opts.c
index da783e4990c..fa8cd0ccb09 100644
--- gcc/c-family/c-opts.c
+++ gcc/c-family/c-opts.c
@@ -919,6 +919,10 @@ c_common_post_options (const char **pfilename)
if (!global_options_set.x_warn_comma_subscript)
warn_comma_subscript = (cxx_dialect >= cxx2a && warn_deprecated);
+ /* -Wvolatile is enabled by default in C++20. */
+ if (!global_options_set.x_warn_volatile)
+ warn_volatile = (cxx_dialect >= cxx2a && warn_deprecated);
+
/* Declone C++ 'structors if -Os. */
if (flag_declone_ctor_dtor == -1)
flag_declone_ctor_dtor = optimize_size;
diff --git gcc/c-family/c.opt gcc/c-family/c.opt
index 257cadfa5f1..5adb3c1bcd5 100644
--- gcc/c-family/c.opt
+++ gcc/c-family/c.opt
@@ -1221,6 +1221,10 @@ Wno-vla-larger-than
C ObjC C++ LTO ObjC++ Alias(Wvla-larger-than=,18446744073709551615EiB,none)
Warning
-Wno-vla-larger-than Disable Wvla-larger-than= warning. Equivalent to
Wvla-larger-than=<SIZE_MAX> or larger.
+Wvolatile
+C++ ObjC++ Var(warn_volatile) Warning
+Warn about certain uses of volatile qualifier.
Maybe "deprecated uses"?
+
Wvolatile-register-var
C ObjC C++ ObjC++ Var(warn_volatile_register_var) Warning LangEnabledBy(C
ObjC C++ ObjC++,Wall)
Warn when a register variable is declared volatile.
diff --git gcc/cp/cp-gimplify.c gcc/cp/cp-gimplify.c
index 065dcb7ba06..49fa47ac3af 100644
--- gcc/cp/cp-gimplify.c
+++ gcc/cp/cp-gimplify.c
@@ -2507,6 +2507,9 @@ cp_fold (tree x)
else
x = org_x;
}
+ if (code == MODIFY_EXPR && TREE_CODE (x) == MODIFY_EXPR)
+ TREE_THIS_VOLATILE (x) = TREE_THIS_VOLATILE (org_x);
+
break;
case VEC_COND_EXPR:
diff --git gcc/cp/decl.c gcc/cp/decl.c
index 9f7923871db..de312c47c21 100644
--- gcc/cp/decl.c
+++ gcc/cp/decl.c
@@ -11189,6 +11189,10 @@ grokdeclarator (const cp_declarator *declarator,
if (concept_p)
error_at (declspecs->locations[ds_concept],
"structured binding declaration cannot be %qs", "concept");
+ /* [dcl.struct.bind] "A cv that includes volatile is deprecated." */
+ if (type_quals & TYPE_QUAL_VOLATILE)
+ warning_at (declspecs->locations[ds_volatile], OPT_Wvolatile,
+ "%<volatile%>-qualified structured binding is deprecated");
switch (storage_class)
{
case sc_none:
@@ -11579,6 +11583,13 @@ grokdeclarator (const cp_declarator *declarator,
if (SCALAR_TYPE_P (type) || VOID_TYPE_P (type))
warning_at (typespec_loc, OPT_Wignored_qualifiers, "type "
"qualifiers ignored on function return type");
+ /* [dcl.fct] "A volatile-qualified return type is
+ deprecated." */
+ if (type_quals & TYPE_QUAL_VOLATILE)
+ warning_at (typespec_loc, OPT_Wvolatile,
+ "%<volatile%>-qualified return type is "
+ "deprecated");
+
/* We now know that the TYPE_QUALS don't apply to the
decl, but to its return type. */
type_quals = TYPE_UNQUALIFIED;
@@ -13320,6 +13331,13 @@ grokparms (tree parmlist, tree *parms)
cp_warn_deprecated_use (deptype);
}
+ /* [dcl.fct] "A parameter with volatile-qualified type is
+ deprecated." */
+ if (CP_TYPE_VOLATILE_P (type))
+ warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wvolatile,
+ "%<volatile%>-qualified parameter is "
+ "deprecated");
+
/* Top-level qualifiers on the parameters are
ignored for function types. */
type = cp_build_qualified_type (type, 0);
diff --git gcc/cp/expr.c gcc/cp/expr.c
index 9160043ed11..bb5097c988d 100644
--- gcc/cp/expr.c
+++ gcc/cp/expr.c
@@ -207,6 +207,27 @@ mark_use (tree expr, bool rvalue_p, bool read_p,
recurse_op[0] = true;
break;
+ case MODIFY_EXPR:
+ {
+ tree lhs = TREE_OPERAND (expr, 0);
+ /* [expr.ass] "A simple assignment whose left operand is of
+ a volatile-qualified type is deprecated unless the assignment
+ is either a discarded-value expression or appears in an
+ unevaluated context." */
+ if (read_p
+ && (TREE_THIS_VOLATILE (lhs)
+ || CP_TYPE_VOLATILE_P (TREE_TYPE (lhs)))
+ && !TREE_THIS_VOLATILE (expr))
+ {
+ warning_at (location_of (expr), OPT_Wvolatile,
+ "assignment with %<volatile%>-qualified left "
+ "operand is deprecated");
This should be more specific; the assignment itself isn't deprecated,
but rather using the assignment as an lvalue or rvalue.
+ /* Make sure not to warn about this assignment again. */
+ TREE_THIS_VOLATILE (expr) = true;
+ }
+ break;
+ }
+
default:
break;
}
diff --git gcc/cp/typeck.c gcc/cp/typeck.c
index e2a4f285a72..0acdf4e3426 100644
--- gcc/cp/typeck.c
+++ gcc/cp/typeck.c
@@ -6459,6 +6459,17 @@ cp_build_unary_op (enum tree_code code, tree xarg, bool
noconvert,
complain))
return error_mark_node;
+ /* [depr.volatile.type] "Postfix ++ and -- expressions and
+ prefix ++ and -- expressions of volatile-qualified arithmetic
+ and pointer types are deprecated." */
+ if (TREE_THIS_VOLATILE (arg) || CP_TYPE_VOLATILE_P (TREE_TYPE (arg)))
+ warning_at (location, OPT_Wvolatile,
+ "%qs expression of %<volatile%>-qualified type is "
+ "deprecated",
+ ((code == PREINCREMENT_EXPR
+ || code == POSTINCREMENT_EXPR)
+ ? "++" : "--"));
+
/* Forbid using -- or ++ in C++17 on `bool'. */
if (TREE_CODE (declared_type) == BOOLEAN_TYPE)
{
@@ -8278,6 +8289,15 @@ cp_build_modify_expr (location_t loc, tree lhs, enum
tree_code modifycode,
&& MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
|| MAYBE_CLASS_TYPE_P (lhstype)));
+ /* An expression of the form E1 op= E2. [expr.ass] says:
+ "Such expressions are deprecated if E1 has volatile-qualified
+ type." We warn here rather than in cp_genericize_r because
+ for compound assignments we are supposed to warn even if the
+ assignment is a discarded-value expression. */
+ if (TREE_THIS_VOLATILE (lhs) || CP_TYPE_VOLATILE_P (lhstype))
+ warning_at (loc, OPT_Wvolatile,
+ "assignment with %<volatile%>-qualified left operand "
+ "is deprecated");
And this should say "compound assignment ..."
/* Preevaluate the RHS to make sure its evaluation is complete
before the lvalue-to-rvalue conversion of the LHS:
@@ -8450,8 +8470,8 @@ cp_build_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
goto ret;
}
- result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
- lhstype, lhs, newrhs);
+ result = build2_loc (loc, modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
+ lhstype, lhs, newrhs);
TREE_SIDE_EFFECTS (result) = 1;
if (!plain_assign)
diff --git gcc/doc/invoke.texi gcc/doc/invoke.texi
index 549e043c67c..0ea2ae284ca 100644
--- gcc/doc/invoke.texi
+++ gcc/doc/invoke.texi
@@ -243,7 +243,7 @@ in the following sections.
-Wno-non-template-friend -Wold-style-cast @gol
-Woverloaded-virtual -Wno-pmf-conversions @gol
-Wno-class-conversion -Wno-terminate @gol
--Wsign-promo -Wvirtual-inheritance}
+-Wsign-promo -Wvirtual-inheritance -Wvolatile}
@item Objective-C and Objective-C++ Language Options
@xref{Objective-C and Objective-C++ Dialect Options,,Options Controlling
@@ -3515,6 +3515,18 @@ result in a call to @code{terminate}.
Disable the warning about the case when a conversion function converts an
object to the same type, to a base class of that type, or to void; such
a conversion function will never be called.
+
+@item -Wvolatile @r{(C++ and Objective-C++ only)}
+@opindex Wvolatile
+@opindex Wno-volatile
+Warn about certain uses of volatile qualifier. This includes postfix
+@code{++} and @code{--} expressions, prefix @code{++} and @code{--}
+expressions, certain assignments where the left operand is a
+volatile-qualified non-class type
This should also be more specific.
, volatile-qualified function return
+type, volatile-qualified parameter type, and a structured binding
+of a volatile-qualified type. This usage was deprecated in C++2a.
+
+Enabled by default with @option{-std=c++2a}.
@end table
@node Objective-C and Objective-C++ Dialect Options
diff --git gcc/testsuite/c-c++-common/Wbool-operation-1.c
gcc/testsuite/c-c++-common/Wbool-operation-1.c
index 04891878155..ce87705692a 100644
--- gcc/testsuite/c-c++-common/Wbool-operation-1.c
+++ gcc/testsuite/c-c++-common/Wbool-operation-1.c
@@ -1,6 +1,7 @@
/* PR c/77490 */
/* { dg-do compile } */
/* { dg-options "-Wall -Wno-psabi" } */
+/* { dg-additional-options "-Wno-volatile" { target c++ } } */
#ifndef __cplusplus
# define bool _Bool
diff --git gcc/testsuite/c-c++-common/gomp/atomic-1.c
gcc/testsuite/c-c++-common/gomp/atomic-1.c
index 3e4bc569ba7..1facf4586f5 100644
--- gcc/testsuite/c-c++-common/gomp/atomic-1.c
+++ gcc/testsuite/c-c++-common/gomp/atomic-1.c
@@ -1,4 +1,5 @@
/* { dg-do compile } */
+/* { dg-additional-options "-Wno-volatile" { target c++ } } */
int x;
volatile int y;
diff --git gcc/testsuite/c-c++-common/gomp/atomic-9.c
gcc/testsuite/c-c++-common/gomp/atomic-9.c
index c07da8fc712..35548395f36 100644
--- gcc/testsuite/c-c++-common/gomp/atomic-9.c
+++ gcc/testsuite/c-c++-common/gomp/atomic-9.c
@@ -1,5 +1,6 @@
/* { dg-do compile } */
/* { dg-options "-fopenmp -fdump-tree-ompexp" } */
+/* { dg-additional-options "-Wno-volatile" { target c++ } } */
/* { dg-require-effective-target cas_int } */
volatile int *bar(void);
diff --git gcc/testsuite/c-c++-common/gomp/depend-iterator-1.c
gcc/testsuite/c-c++-common/gomp/depend-iterator-1.c
index 4fb01c174ec..6fa60215f43 100644
--- gcc/testsuite/c-c++-common/gomp/depend-iterator-1.c
+++ gcc/testsuite/c-c++-common/gomp/depend-iterator-1.c
@@ -1,3 +1,5 @@
+/* { dg-additional-options "-Wno-volatile" { target c++ } } */
+
int arr[64], arr2[64];
struct S { int a[4]; } k;
short arr4[4];
diff --git gcc/testsuite/c-c++-common/gomp/loop-1.c
gcc/testsuite/c-c++-common/gomp/loop-1.c
index d2f943aea54..4fb995c02a7 100644
--- gcc/testsuite/c-c++-common/gomp/loop-1.c
+++ gcc/testsuite/c-c++-common/gomp/loop-1.c
@@ -100,8 +100,8 @@ f4 (int *a)
#pragma omp loop order(concurrent) bind(parallel)
for (i = 0; i < 64; i++)
{
- #pragma omp atomic read
- a[i] = v; /* { dg-error "OpenMP constructs
other than 'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" }
*/
+ #pragma omp atomic read /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" "" { target
c++ } } */
+ a[i] = v; /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" "" { target c
} } */
}
#pragma omp loop order(concurrent) bind(parallel)
for (i = 0; i < 64; i++)
@@ -172,8 +172,8 @@ f5 (int *a)
#pragma omp loop
for (i = 0; i < 64; i++)
{
- #pragma omp atomic read
- a[i] = v; /* { dg-error "OpenMP constructs
other than 'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" }
*/
+ #pragma omp atomic read /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" "" { target
c++ } } */
+ a[i] = v; /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" "" { target c
} } */
}
#pragma omp loop
for (i = 0; i < 64; i++)
@@ -245,8 +245,8 @@ f6 (int *a)
#pragma omp loop
for (i = 0; i < 64; i++)
{
- #pragma omp atomic read
- a[i] = v; /* { dg-error "OpenMP constructs
other than 'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" }
*/
+ #pragma omp atomic read /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" "" { target
c++ } } */
+ a[i] = v; /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a 'loop' region" "" { target c
} } */
}
#pragma omp loop
for (i = 0; i < 64; i++)
diff --git gcc/testsuite/c-c++-common/gomp/order-3.c
gcc/testsuite/c-c++-common/gomp/order-3.c
index 2d51bf37749..e33386dd5cc 100644
--- gcc/testsuite/c-c++-common/gomp/order-3.c
+++ gcc/testsuite/c-c++-common/gomp/order-3.c
@@ -50,8 +50,8 @@ f1 (int *a)
#pragma omp simd order(concurrent)
for (i = 0; i < 64; i++)
{
- #pragma omp atomic read
- a[i] = v; /* { dg-error "OpenMP constructs
other than 'parallel', 'loop' or 'simd' may not be nested inside a region with the
'order\\(concurrent\\)' clause" } */
+ #pragma omp atomic read /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a region with the 'order\\(concurrent\\)'
clause" "" { target c++ } } */
+ a[i] = v; /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a region with the 'order\\(concurrent\\)'
clause" "" { target c } } */
}
#pragma omp simd order(concurrent)
for (i = 0; i < 64; i++)
@@ -112,8 +112,8 @@ f2 (int *a)
#pragma omp for simd order(concurrent)
for (i = 0; i < 64; i++)
{
- #pragma omp atomic read
- a[i] = v; /* { dg-error "OpenMP constructs
other than 'parallel', 'loop' or 'simd' may not be nested inside a region with the
'order\\(concurrent\\)' clause" } */
+ #pragma omp atomic read /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a region with the 'order\\(concurrent\\)'
clause" "" { target c++ } } */
+ a[i] = v; /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a region with the 'order\\(concurrent\\)'
clause" "" { target c } } */
}
#pragma omp for simd order(concurrent)
for (i = 0; i < 64; i++)
@@ -174,8 +174,8 @@ f3 (int *a)
#pragma omp for order(concurrent)
for (i = 0; i < 64; i++)
{
- #pragma omp atomic read
- a[i] = v; /* { dg-error "OpenMP constructs
other than 'parallel', 'loop' or 'simd' may not be nested inside a region with the
'order\\(concurrent\\)' clause" } */
+ #pragma omp atomic read /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a region with the 'order\\(concurrent\\)'
clause" "" { target c++ } } */
+ a[i] = v; /* { dg-error "OpenMP constructs other than
'parallel', 'loop' or 'simd' may not be nested inside a region with the 'order\\(concurrent\\)'
clause" "" { target c } } */
}
#pragma omp for order(concurrent)
for (i = 0; i < 64; i++)
diff --git gcc/testsuite/c-c++-common/pr69733.c
gcc/testsuite/c-c++-common/pr69733.c
index 57ec1eccb9f..ab70f49009c 100644
--- gcc/testsuite/c-c++-common/pr69733.c
+++ gcc/testsuite/c-c++-common/pr69733.c
@@ -1,5 +1,6 @@
/* { dg-do compile } */
/* { dg-options "-W -fdiagnostics-show-caret" } */
+/* { dg-additional-options "-Wno-volatile" { target c++ } } */
typedef const double cd;
double val;
@@ -21,4 +22,3 @@ cd val2() {return val;} /* { dg-warning "qualifiers ignored"
} */
cd val2() {return val;}
^~
{ dg-end-multiline-output "" } */
-
diff --git gcc/testsuite/c-c++-common/spec-barrier-2.c
gcc/testsuite/c-c++-common/spec-barrier-2.c
index b09567e62a9..a27ec54f0d3 100644
--- gcc/testsuite/c-c++-common/spec-barrier-2.c
+++ gcc/testsuite/c-c++-common/spec-barrier-2.c
@@ -1,4 +1,5 @@
/* { dg-do run } */
+/* { dg-additional-options "-Wno-volatile" { target c++ } } */
/* Even on targets that don't need the optional failval parameter,
side-effects on the operand should still be calculated. */
diff --git gcc/testsuite/c-c++-common/tm/pr54893.c
gcc/testsuite/c-c++-common/tm/pr54893.c
index 3766078d31e..266cbe9c652 100644
--- gcc/testsuite/c-c++-common/tm/pr54893.c
+++ gcc/testsuite/c-c++-common/tm/pr54893.c
@@ -1,5 +1,6 @@
/* { dg-do compile } */
/* { dg-options "-fgnu-tm -fdump-ipa-tmipa" } */
+/* { dg-additional-options "-Wno-volatile" { target c++ } } */
/* Test that volatiles are allowed inside relaxed transactions. */
diff --git gcc/testsuite/g++.dg/cpp0x/pr65327.C gcc/testsuite/g++.dg/cpp0x/pr65327.C
index 5176b3c3204..6e888ebff2c 100644
--- gcc/testsuite/g++.dg/cpp0x/pr65327.C
+++ gcc/testsuite/g++.dg/cpp0x/pr65327.C
@@ -11,7 +11,7 @@ foo ()
static constexpr volatile int k = 5;
}
-constexpr volatile int
+constexpr volatile int // { dg-warning "deprecated" "" { target c++2a } }
bar ()
{
return i;
diff --git gcc/testsuite/g++.dg/cpp0x/rv-conv2.C
gcc/testsuite/g++.dg/cpp0x/rv-conv2.C
index 9b9b154995b..2f2a1fa702a 100644
--- gcc/testsuite/g++.dg/cpp0x/rv-conv2.C
+++ gcc/testsuite/g++.dg/cpp0x/rv-conv2.C
@@ -1,16 +1,16 @@
// PR c++/89705
// { dg-do compile { target c++11 } }
-struct W { operator const volatile int(); };
+struct W { operator const volatile int(); }; // { dg-warning "deprecated" "" {
target c++2a } }
const int& rci = W();
struct X { operator const int(); };
int&& rri = X();
-struct Y { operator volatile int(); };
+struct Y { operator volatile int(); }; // { dg-warning "deprecated" "" {
target c++2a } }
int&& rri2 = Y();
-struct Z { operator const volatile int(); };
+struct Z { operator const volatile int(); }; // { dg-warning "deprecated" "" {
target c++2a } }
volatile int&& rri3 = Z();
enum E { A };
diff --git gcc/testsuite/g++.dg/cpp0x/rv1n.C gcc/testsuite/g++.dg/cpp0x/rv1n.C
index f5e75681758..a762fc85862 100644
--- gcc/testsuite/g++.dg/cpp0x/rv1n.C
+++ gcc/testsuite/g++.dg/cpp0x/rv1n.C
@@ -26,8 +26,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 1 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv1p.C gcc/testsuite/g++.dg/cpp0x/rv1p.C
index a9097276d5a..e2a983a7708 100644
--- gcc/testsuite/g++.dg/cpp0x/rv1p.C
+++ gcc/testsuite/g++.dg/cpp0x/rv1p.C
@@ -26,8 +26,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 1 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv2n.C gcc/testsuite/g++.dg/cpp0x/rv2n.C
index 65eda80fba0..2871ccf9ab3 100644
--- gcc/testsuite/g++.dg/cpp0x/rv2n.C
+++ gcc/testsuite/g++.dg/cpp0x/rv2n.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 2 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv2p.C gcc/testsuite/g++.dg/cpp0x/rv2p.C
index 25a42ba2af8..bab0dce3d97 100644
--- gcc/testsuite/g++.dg/cpp0x/rv2p.C
+++ gcc/testsuite/g++.dg/cpp0x/rv2p.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 2 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv3n.C gcc/testsuite/g++.dg/cpp0x/rv3n.C
index 4549438f8ef..35cdba95858 100644
--- gcc/testsuite/g++.dg/cpp0x/rv3n.C
+++ gcc/testsuite/g++.dg/cpp0x/rv3n.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 3 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv3p.C gcc/testsuite/g++.dg/cpp0x/rv3p.C
index 2d7d78df6be..b25aa26c9b0 100644
--- gcc/testsuite/g++.dg/cpp0x/rv3p.C
+++ gcc/testsuite/g++.dg/cpp0x/rv3p.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 3 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv4n.C gcc/testsuite/g++.dg/cpp0x/rv4n.C
index 29deb3fc81b..6941a13de6c 100644
--- gcc/testsuite/g++.dg/cpp0x/rv4n.C
+++ gcc/testsuite/g++.dg/cpp0x/rv4n.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 4 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv4p.C gcc/testsuite/g++.dg/cpp0x/rv4p.C
index 0e4903bc291..cd0d631d780 100644
--- gcc/testsuite/g++.dg/cpp0x/rv4p.C
+++ gcc/testsuite/g++.dg/cpp0x/rv4p.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 4 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv5n.C gcc/testsuite/g++.dg/cpp0x/rv5n.C
index f11d07a3921..086aa460c68 100644
--- gcc/testsuite/g++.dg/cpp0x/rv5n.C
+++ gcc/testsuite/g++.dg/cpp0x/rv5n.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 5 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv5p.C gcc/testsuite/g++.dg/cpp0x/rv5p.C
index 63441a3f0da..34c1017f578 100644
--- gcc/testsuite/g++.dg/cpp0x/rv5p.C
+++ gcc/testsuite/g++.dg/cpp0x/rv5p.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 5 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv6n.C gcc/testsuite/g++.dg/cpp0x/rv6n.C
index 0ebbe33e1d1..b21d22a5b87 100644
--- gcc/testsuite/g++.dg/cpp0x/rv6n.C
+++ gcc/testsuite/g++.dg/cpp0x/rv6n.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 6 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv6p.C gcc/testsuite/g++.dg/cpp0x/rv6p.C
index 26714f0c9aa..fee692bb08f 100644
--- gcc/testsuite/g++.dg/cpp0x/rv6p.C
+++ gcc/testsuite/g++.dg/cpp0x/rv6p.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 6 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv7n.C gcc/testsuite/g++.dg/cpp0x/rv7n.C
index d9e371b8adb..5bc313cc07f 100644
--- gcc/testsuite/g++.dg/cpp0x/rv7n.C
+++ gcc/testsuite/g++.dg/cpp0x/rv7n.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 7 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv7p.C gcc/testsuite/g++.dg/cpp0x/rv7p.C
index 60a35835c7d..b0b8f965498 100644
--- gcc/testsuite/g++.dg/cpp0x/rv7p.C
+++ gcc/testsuite/g++.dg/cpp0x/rv7p.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 7 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/rv8p.C gcc/testsuite/g++.dg/cpp0x/rv8p.C
index e12da4b8d79..287fb93b432 100644
--- gcc/testsuite/g++.dg/cpp0x/rv8p.C
+++ gcc/testsuite/g++.dg/cpp0x/rv8p.C
@@ -25,8 +25,8 @@ struct A
A source();
const A c_source();
- volatile A v_source();
-const volatile A cv_source();
+ volatile A v_source(); // { dg-warning "deprecated" "" { target c++2a }
}
+const volatile A cv_source(); // { dg-warning "deprecated" "" { target c++2a }
}
// 8 at a time
diff --git gcc/testsuite/g++.dg/cpp0x/trailing14.C gcc/testsuite/g++.dg/cpp0x/trailing14.C
index 2544d0bab5e..4ebb37406ad 100644
--- gcc/testsuite/g++.dg/cpp0x/trailing14.C
+++ gcc/testsuite/g++.dg/cpp0x/trailing14.C
@@ -1,6 +1,6 @@
// PR c++/65775
// { dg-do compile { target c++11 } }
-// { dg-options "-Wignored-qualifiers" }
+// { dg-options "-Wignored-qualifiers -Wno-volatile" }
using Qi = int const volatile;
Qi q1(); // { dg-warning "1: type qualifiers ignored" }
diff --git gcc/testsuite/g++.dg/cpp1y/new1.C gcc/testsuite/g++.dg/cpp1y/new1.C
index 5e4f1bf6b0b..b9ad64dfcc0 100644
--- gcc/testsuite/g++.dg/cpp1y/new1.C
+++ gcc/testsuite/g++.dg/cpp1y/new1.C
@@ -65,7 +65,7 @@ void
test_unused() {
volatile double d = 0.0;
double *p = new double ();
- d += 1.0;
+ d += 1.0; // { dg-warning "deprecated" "" { target c++2a } }
delete p;
}
diff --git gcc/testsuite/g++.dg/cpp2a/volatile1.C gcc/testsuite/g++.dg/cpp2a/volatile1.C
new file mode 100644
index 00000000000..16c3bb417d3
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp2a/volatile1.C
@@ -0,0 +1,140 @@
+// PR c++/91361 - P1152R4: Deprecating some uses of volatile.
+// { dg-do compile { target c++17 } }
+
+#define ACCESS_ONCE(x) (*(volatile __typeof(x) *)&(x))
+
+struct S {
+ volatile int a : 4;
+ int b : 2;
+};
+
+struct T {
+ int a : 4;
+ int b : 2;
+};
+
+union U {
+ char c;
+ int i;
+};
+
+struct W {
+ W();
+ W(volatile W&);
+ W& operator=(volatile W&) volatile;
+};
+
+volatile int // { dg-warning ".volatile.-qualified return type is deprecated"
"" { target c++2a } }
+fn (volatile int i) // { dg-warning ".volatile.-qualified parameter is deprecated"
"" { target c++2a } }
+{
+ volatile int v = 10;
+ int *volatile p = nullptr;
+
+ // Pre/post ++/--.
+ v++; // { dg-warning "expression of .volatile.-qualified type is deprecated"
"" { target c++2a } }
+ ++v; // { dg-warning "expression of .volatile.-qualified type is deprecated"
"" { target c++2a } }
+ v--; // { dg-warning "expression of .volatile.-qualified type is deprecated"
"" { target c++2a } }
+ --v; // { dg-warning "expression of .volatile.-qualified type is deprecated"
"" { target c++2a } }
+ p++; // { dg-warning "expression of .volatile.-qualified type is deprecated"
"" { target c++2a } }
+ ++p; // { dg-warning "expression of .volatile.-qualified type is deprecated"
"" { target c++2a } }
+ p--; // { dg-warning "expression of .volatile.-qualified type is deprecated"
"" { target c++2a } }
+ --p; // { dg-warning "expression of .volatile.-qualified type is deprecated"
"" { target c++2a } }
+ return v + i + *p;
+}
+
+void
+fn2 ()
+{
+ volatile int vi = 42;
+ int i = 24;
+
+ // Discarded-value expression ([expr.context]).
+ // The lvalue-to-rvalue conversion is applied here:
+ vi;
+ // ...but not here. Otherwise we'd write to VI and then immediately read it.
+ vi = 42;
+ vi = i;
+ vi = i = 42;
+ i = vi = 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ &(vi = i); // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ (vi = 42, 45);
+ (i = vi = 42, 10); // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ i = vi; // LHS not volatile.
+ i = (vi = i, 42);
+ static_cast<void>(vi = i);
+ static_cast<void>(i = vi = 42); // { dg-warning "assignment with .volatile.-qualified left
operand is deprecated" "" { target c++2a } }
+ (void)(vi = i);
+ (void)(i = vi = 42); // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+
+ // Unevaluated operand.
+ decltype(vi = 42) x = vi;
I guess we should also test that there's no warning for
decltype(i = vi = 42)
since this is also an unevaluated context. It's a bit odd the proposal
uses "unevaluated context" rather than "unevaluated operand".
+
+ // Compound assignments.
+ vi += i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ vi -= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ vi %= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ vi ^= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ vi |= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ vi /= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ vi = vi += 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ vi += vi = 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ i *= vi;
+ decltype(vi -= 42) x2 = vi; // { dg-warning "assignment with .volatile.-qualified left
operand is deprecated" "" { target c++2a } }
+
+ // Structured bindings.
+ int a[] = { 10, 5 };
+ const auto & [cxr, cyr] = a;
+ const volatile auto & [cvxr, cvyr] = a; // { dg-warning ".volatile.-qualified structured
binding is deprecated" "" { target c++2a } }
+ volatile auto & [vxr, vyr] = a; // { dg-warning ".volatile.-qualified structured binding is
deprecated" "" { target c++2a } }
+}
+
+void
+fn3 ()
+{
+ volatile int i, j, k = 0;
+ i = j = k; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+
+ ACCESS_ONCE(j);
+
+ S s;
+ s.b = 1;
+
+ volatile U u;
+ u.c = 42;
+ i = u.c = 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ u.c += 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+
+ volatile T t;
+ t.a = 3;
+ j = t.a = 3; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ t.a += 3; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+
+ volatile int *src = &i;
+ *src; // No assignment, don't warn.
+}
+
+void
+fn4 ()
+{
+ volatile W vw;
+ W w;
+ // Assignment to objects of a class is defined by the copy/move assignment
+ // operator.
+ vw = w;
+ w = vw;
+}
+
+template<typename T>
+void raccoon ()
+{
+ volatile T t, u;
+ t = 42;
+ u = t = 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+ t &= 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" "" { target c++2a } }
+}
+
+void
+fn5 ()
+{
+ raccoon<int>();
+}
diff --git gcc/testsuite/g++.dg/cpp2a/volatile2.C
gcc/testsuite/g++.dg/cpp2a/volatile2.C
new file mode 100644
index 00000000000..31035e22d8f
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp2a/volatile2.C
@@ -0,0 +1,141 @@
+// PR c++/91361 - P1152R4: Deprecating some uses of volatile.
+// { dg-do compile { target c++2a } }
+// { dg-options "-Wno-volatile" }
+
+#define ACCESS_ONCE(x) (*(volatile __typeof(x) *)&(x))
+
+struct S {
+ volatile int a : 4;
+ int b : 2;
+};
+
+struct T {
+ int a : 4;
+ int b : 2;
+};
+
+union U {
+ char c;
+ int i;
+};
+
+struct W {
+ W();
+ W(volatile W&);
+ W& operator=(volatile W&) volatile;
+};
+
+volatile int
+fn (volatile int i)
+{
+ volatile int v = 10;
+ int *volatile p = nullptr;
+
+ // Pre/post ++/--.
+ v++;
+ ++v;
+ v--;
+ --v;
+ p++;
+ ++p;
+ p--;
+ --p;
+ return v + i + *p;
+}
+
+void
+fn2 ()
+{
+ volatile int vi = 42;
+ int i = 24;
+
+ // Discarded-value expression ([expr.context]).
+ // The lvalue-to-rvalue conversion is applied here:
+ vi;
+ // ...but not here. Otherwise we'd write to VI and then immediately read it.
+ vi = 42;
+ vi = i;
+ vi = i = 42;
+ i = vi = 42;
+ &(vi = i);
+ (vi = 42, 45);
+ (i = vi = 42, 10);
+ i = vi; // LHS not volatile.
+ i = (vi = i, 42);
+ static_cast<void>(vi = i);
+ static_cast<void>(i = vi = 42);
+ (void)(vi = i);
+ (void)(i = vi = 42);
+
+ // Unevaluated operand.
+ decltype(vi = 42) x = vi;
+
+ // Compound assignments.
+ vi += i;
+ vi -= i;
+ vi %= i;
+ vi ^= i;
+ vi |= i;
+ vi /= i;
+ vi = vi += 42;
+ vi += vi = 42;
+ i *= vi;
+ decltype(vi -= 42) x2 = vi;
+
+ // Structured bindings.
+ int a[] = { 10, 5 };
+ const auto & [cxr, cyr] = a;
+ const volatile auto & [cvxr, cvyr] = a;
+ volatile auto & [vxr, vyr] = a;
+}
+
+void
+fn3 ()
+{
+ volatile int i, j, k = 0;
+ i = j = k;
+
+ ACCESS_ONCE(j);
+
+ S s;
+ s.b = 1;
+
+ volatile U u;
+ u.c = 42;
+ i = u.c = 42;
+ u.c += 42;
+
+ volatile T t;
+ t.a = 3;
+ j = t.a = 3;
+ t.a += 3;
+
+ volatile int *src = &i;
+ *src; // No assignment, don't warn.
+}
+
+void
+fn4 ()
+{
+ volatile W vw;
+ W w;
+ // Assignment to objects of a class is defined by the copy/move assignment
+ // operator.
+ vw = w;
+ w = vw;
+}
+
+template<typename T>
+void raccoon ()
+{
+ volatile T t, u;
+ t = 42;
+ u = t = 42;
+ t &= 42;
+}
+
+void
+fn5 ()
+{
+ raccoon<int>();
+}
diff --git gcc/testsuite/g++.dg/cpp2a/volatile3.C
gcc/testsuite/g++.dg/cpp2a/volatile3.C
new file mode 100644
index 00000000000..731c9aec99f
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp2a/volatile3.C
@@ -0,0 +1,141 @@
+// PR c++/91361 - P1152R4: Deprecating some uses of volatile.
+// { dg-do compile { target c++17 } }
+// { dg-options "-Wvolatile" }
+
+#define ACCESS_ONCE(x) (*(volatile __typeof(x) *)&(x))
+
+struct S {
+ volatile int a : 4;
+ int b : 2;
+};
+
+struct T {
+ int a : 4;
+ int b : 2;
+};
+
+union U {
+ char c;
+ int i;
+};
+
+struct W {
+ W();
+ W(volatile W&);
+ W& operator=(volatile W&) volatile;
+};
+
+volatile int // { dg-warning ".volatile.-qualified return type is deprecated" }
+fn (volatile int i) // { dg-warning ".volatile.-qualified parameter is
deprecated" }
+{
+ volatile int v = 10;
+ int *volatile p = nullptr;
+
+ // Pre/post ++/--.
+ v++; // { dg-warning "expression of .volatile.-qualified type is deprecated"
}
+ ++v; // { dg-warning "expression of .volatile.-qualified type is deprecated"
}
+ v--; // { dg-warning "expression of .volatile.-qualified type is deprecated"
}
+ --v; // { dg-warning "expression of .volatile.-qualified type is deprecated"
}
+ p++; // { dg-warning "expression of .volatile.-qualified type is deprecated"
}
+ ++p; // { dg-warning "expression of .volatile.-qualified type is deprecated"
}
+ p--; // { dg-warning "expression of .volatile.-qualified type is deprecated"
}
+ --p; // { dg-warning "expression of .volatile.-qualified type is deprecated"
}
+ return v + i + *p;
+}
+
+void
+fn2 ()
+{
+ volatile int vi = 42;
+ int i = 24;
+
+ // Discarded-value expression ([expr.context]).
+ // The lvalue-to-rvalue conversion is applied here:
+ vi;
+ // ...but not here. Otherwise we'd write to VI and then immediately read it.
+ vi = 42;
+ vi = i;
+ vi = i = 42;
+ i = vi = 42; // { dg-warning "assignment with .volatile.-qualified left operand
is deprecated" }
+ &(vi = i); // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+ (vi = 42, 45);
+ (i = vi = 42, 10); // { dg-warning "assignment with .volatile.-qualified left
operand is deprecated" }
+ i = vi; // LHS not volatile.
+ i = (vi = i, 42);
+ static_cast<void>(vi = i);
+ static_cast<void>(i = vi = 42); // { dg-warning "assignment with
.volatile.-qualified left operand is deprecated" }
+ (void)(vi = i);
+ (void)(i = vi = 42); // { dg-warning "assignment with .volatile.-qualified left
operand is deprecated" }
+
+ // Unevaluated operand.
+ decltype(vi = 42) x = vi;
+
+ // Compound assignments.
+ vi += i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+ vi -= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+ vi %= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+ vi ^= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+ vi |= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+ vi /= i; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+ vi = vi += 42; // { dg-warning "assignment with .volatile.-qualified left operand
is deprecated" }
+ vi += vi = 42; // { dg-warning "assignment with .volatile.-qualified left operand
is deprecated" }
+ i *= vi;
+ decltype(vi -= 42) x2 = vi; // { dg-warning "assignment with .volatile.-qualified
left operand is deprecated" }
+
+ // Structured bindings.
+ int a[] = { 10, 5 };
+ const auto & [cxr, cyr] = a;
+ const volatile auto & [cvxr, cvyr] = a; // { dg-warning ".volatile.-qualified
structured binding is deprecated" }
+ volatile auto & [vxr, vyr] = a; // { dg-warning ".volatile.-qualified structured
binding is deprecated" }
+}
+
+void
+fn3 ()
+{
+ volatile int i, j, k = 0;
+ i = j = k; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+
+ ACCESS_ONCE(j);
+
+ S s;
+ s.b = 1;
+
+ volatile U u;
+ u.c = 42;
+ i = u.c = 42; // { dg-warning "assignment with .volatile.-qualified left operand
is deprecated" }
+ u.c += 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+
+ volatile T t;
+ t.a = 3;
+ j = t.a = 3; // { dg-warning "assignment with .volatile.-qualified left operand
is deprecated" }
+ t.a += 3; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+
+ volatile int *src = &i;
+ *src; // No assignment, don't warn.
+}
+
+void
+fn4 ()
+{
+ volatile W vw;
+ W w;
+ // Assignment to objects of a class is defined by the copy/move assignment
+ // operator.
+ vw = w;
+ w = vw;
+}
+
+template<typename T>
+void raccoon ()
+{
+ volatile T t, u;
+ t = 42;
+ u = t = 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+ t &= 42; // { dg-warning "assignment with .volatile.-qualified left operand is
deprecated" }
+}
+
+void
+fn5 ()
+{
+ raccoon<int>();
+}
diff --git gcc/testsuite/g++.dg/cpp2a/volatile4.C
gcc/testsuite/g++.dg/cpp2a/volatile4.C
new file mode 100644
index 00000000000..4d039545ac9
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp2a/volatile4.C
@@ -0,0 +1,141 @@
+// PR c++/91361 - P1152R4: Deprecating some uses of volatile.
+// { dg-do compile { target c++2a } }
+// { dg-options "-Wno-deprecated" }
+
+#define ACCESS_ONCE(x) (*(volatile __typeof(x) *)&(x))
+
+struct S {
+ volatile int a : 4;
+ int b : 2;
+};
+
+struct T {
+ int a : 4;
+ int b : 2;
+};
+
+union U {
+ char c;
+ int i;
+};
+
+struct W {
+ W();
+ W(volatile W&);
+ W& operator=(volatile W&) volatile;
+};
+
+volatile int
+fn (volatile int i)
+{
+ volatile int v = 10;
+ int *volatile p = nullptr;
+
+ // Pre/post ++/--.
+ v++;
+ ++v;
+ v--;
+ --v;
+ p++;
+ ++p;
+ p--;
+ --p;
+ return v + i + *p;
+}
+
+void
+fn2 ()
+{
+ volatile int vi = 42;
+ int i = 24;
+
+ // Discarded-value expression ([expr.context]).
+ // The lvalue-to-rvalue conversion is applied here:
+ vi;
+ // ...but not here. Otherwise we'd write to VI and then immediately read it.
+ vi = 42;
+ vi = i;
+ vi = i = 42;
+ i = vi = 42;
+ &(vi = i);
+ (vi = 42, 45);
+ (i = vi = 42, 10);
+ i = vi; // LHS not volatile.
+ i = (vi = i, 42);
+ static_cast<void>(vi = i);
+ static_cast<void>(i = vi = 42);
+ (void)(vi = i);
+ (void)(i = vi = 42);
+
+ // Unevaluated operand.
+ decltype(vi = 42) x = vi;
+
+ // Compound assignments.
+ vi += i;
+ vi -= i;
+ vi %= i;
+ vi ^= i;
+ vi |= i;
+ vi /= i;
+ vi = vi += 42;
+ vi += vi = 42;
+ i *= vi;
+ decltype(vi -= 42) x2 = vi;
+
+ // Structured bindings.
+ int a[] = { 10, 5 };
+ const auto & [cxr, cyr] = a;
+ const volatile auto & [cvxr, cvyr] = a;
+ volatile auto & [vxr, vyr] = a;
+}
+
+void
+fn3 ()
+{
+ volatile int i, j, k = 0;
+ i = j = k;
+
+ ACCESS_ONCE(j);
+
+ S s;
+ s.b = 1;
+
+ volatile U u;
+ u.c = 42;
+ i = u.c = 42;
+ u.c += 42;
+
+ volatile T t;
+ t.a = 3;
+ j = t.a = 3;
+ t.a += 3;
+
+ volatile int *src = &i;
+ *src; // No assignment, don't warn.
+}
+
+void
+fn4 ()
+{
+ volatile W vw;
+ W w;
+ // Assignment to objects of a class is defined by the copy/move assignment
+ // operator.
+ vw = w;
+ w = vw;
+}
+
+template<typename T>
+void raccoon ()
+{
+ volatile T t, u;
+ t = 42;
+ u = t = 42;
+ t &= 42;
+}
+
+void
+fn5 ()
+{
+ raccoon<int>();
+}
diff --git gcc/testsuite/g++.dg/expr/bool3.C gcc/testsuite/g++.dg/expr/bool3.C
index 373c202b800..f27399cfc8a 100644
--- gcc/testsuite/g++.dg/expr/bool3.C
+++ gcc/testsuite/g++.dg/expr/bool3.C
@@ -13,8 +13,10 @@ int main()
b++; // { dg-warning "deprecated" "" { target { ! c++17 } } }
// { dg-error "forbidden" "" { target c++17 } .-1 }
+ // { dg-warning ".volatile.-qualified type is deprecated" "" { target c++2a
} .-2 }
b++; // { dg-warning "deprecated" "" { target { ! c++17 } } }
// { dg-error "forbidden" "" { target c++17 } .-1 }
+ // { dg-warning ".volatile.-qualified type is deprecated" "" { target c++2a
} .-2 }
i = b;
if (i != 1)
abort ();
diff --git gcc/testsuite/g++.dg/expr/bool4.C gcc/testsuite/g++.dg/expr/bool4.C
index dce51ec332e..5891bc311bd 100644
--- gcc/testsuite/g++.dg/expr/bool4.C
+++ gcc/testsuite/g++.dg/expr/bool4.C
@@ -8,6 +8,6 @@ int main()
{
my_bool b = false;
b--; // { dg-error "" }
+ // { dg-warning ".volatile.-qualified type is deprecated" "" { target c++2a
} .-1 }
return 0;
}
-
diff --git gcc/testsuite/g++.dg/expr/cond9.C gcc/testsuite/g++.dg/expr/cond9.C
index b344c1f683a..f7e092e1445 100644
--- gcc/testsuite/g++.dg/expr/cond9.C
+++ gcc/testsuite/g++.dg/expr/cond9.C
@@ -4,7 +4,7 @@ struct A { // { dg-message "A" }
A(int);
};
-void foo(volatile A a) {
+void foo(volatile A a) { // { dg-warning "deprecated" "" { target c++2a } }
1 ? a : 0; // { dg-error "qualifiers|lvalue|no match" }
1 ? 0 : a; // { dg-error "qualifiers|lvalue|no match" }
}
diff --git gcc/testsuite/g++.dg/ext/vector25.C
gcc/testsuite/g++.dg/ext/vector25.C
index 6c1f5d09878..339865d6942 100644
--- gcc/testsuite/g++.dg/ext/vector25.C
+++ gcc/testsuite/g++.dg/ext/vector25.C
@@ -2,5 +2,5 @@ volatile int i __attribute__((vector_size(8)));
void foo()
{
- i += i;
+ i += i; // { dg-warning "deprecated" "" { target c++2a } }
}
diff --git gcc/testsuite/g++.dg/gomp/depend-iterator-1.C
gcc/testsuite/g++.dg/gomp/depend-iterator-1.C
index 6f4aa97ee44..d12670c5159 100644
--- gcc/testsuite/g++.dg/gomp/depend-iterator-1.C
+++ gcc/testsuite/g++.dg/gomp/depend-iterator-1.C
@@ -1,3 +1,5 @@
+// { dg-additional-options "-Wno-volatile" }
+
int arr[64], arr2[64];
struct S { int a[4]; } k;
short arr4[4];
diff --git gcc/testsuite/g++.dg/inherit/covariant21.C
gcc/testsuite/g++.dg/inherit/covariant21.C
index 42cdf870081..769cb14ecbc 100644
--- gcc/testsuite/g++.dg/inherit/covariant21.C
+++ gcc/testsuite/g++.dg/inherit/covariant21.C
@@ -6,12 +6,12 @@ struct C : A, B {};
struct X
{
- virtual B* foo(volatile int);
+ virtual B* foo(volatile int); // { dg-warning "deprecated" "" { target c++2a
} }
};
struct Y : X
{
- virtual C* foo(volatile int);
+ virtual C* foo(volatile int); // { dg-warning "deprecated" "" { target c++2a
} }
};
-C* Y::foo(volatile int) { return 0; }
+C* Y::foo(volatile int) { return 0; } // { dg-warning "deprecated" "" { target
c++2a } }
diff --git gcc/testsuite/g++.dg/init/ref18.C gcc/testsuite/g++.dg/init/ref18.C
index e704077c26b..81ac76a40d3 100644
--- gcc/testsuite/g++.dg/init/ref18.C
+++ gcc/testsuite/g++.dg/init/ref18.C
@@ -1,6 +1,6 @@
// PR c++/49395
-volatile int foo();
+volatile int foo(); // { dg-warning "deprecated" "" { target c++2a } }
struct A { volatile int i; };
typedef volatile int vi;
diff --git gcc/testsuite/g++.dg/ipa/pr63838.C gcc/testsuite/g++.dg/ipa/pr63838.C
index d23b3133748..5b6b11d70e5 100644
--- gcc/testsuite/g++.dg/ipa/pr63838.C
+++ gcc/testsuite/g++.dg/ipa/pr63838.C
@@ -7,12 +7,12 @@
__attribute__((noinline, noclone)) static void bar (int);
volatile int v;
void (*fn) ();
-struct S { S () { v++; } ~S () { v++; } };
+struct S { S () { v++; } ~S () { v++; } }; // { dg-warning "deprecated" "" {
target c++2a } }
__attribute__((noinline, noclone)) static void
foo (int x)
{
- v++;
+ v++; // { dg-warning "deprecated" "" { target c++2a } }
if (x == 5)
bar (x);
}
@@ -20,7 +20,7 @@ foo (int x)
__attribute__((noinline, noclone)) static void
bar (int x)
{
- v++;
+ v++; // { dg-warning "deprecated" "" { target c++2a } }
if (x == 6)
foo (x);
else if (x == 5)
diff --git gcc/testsuite/g++.dg/overload/rvalue2.C
gcc/testsuite/g++.dg/overload/rvalue2.C
index 8a2290dc293..a829fb5e8cc 100644
--- gcc/testsuite/g++.dg/overload/rvalue2.C
+++ gcc/testsuite/g++.dg/overload/rvalue2.C
@@ -7,5 +7,5 @@ template <class T> void f(const T&);
int main()
{
volatile int i = 0;
- f(i++);
+ f(i++); // { dg-warning "deprecated" "" { target c++2a } }
}
diff --git gcc/testsuite/g++.dg/parse/semicolon4.C
gcc/testsuite/g++.dg/parse/semicolon4.C
index 5135ec14b1f..bdd1c845187 100644
--- gcc/testsuite/g++.dg/parse/semicolon4.C
+++ gcc/testsuite/g++.dg/parse/semicolon4.C
@@ -25,7 +25,7 @@ struct E1
} const; // { dg-error "'const' can only be specified for
objects and functions" }
void foo (
-struct E2
+struct E2 // { dg-warning "deprecated" "" { target c++2a
} }
{ // { dg-error "types may not be defined in parameter
types" }
int i;
} volatile);
diff --git gcc/testsuite/g++.dg/warn/Wreturn-type-4.C
gcc/testsuite/g++.dg/warn/Wreturn-type-4.C
index 4f02678e7f9..24a6b41cbd8 100644
--- gcc/testsuite/g++.dg/warn/Wreturn-type-4.C
+++ gcc/testsuite/g++.dg/warn/Wreturn-type-4.C
@@ -3,6 +3,7 @@
/* { dg-options "-Wignored-qualifiers" } */
volatile void bar(); /* { dg-warning "type qualifiers ignored" } */
+// { dg-warning ".volatile.-qualified return type is deprecated" "" { target
c++2a } .-1 }
struct A
{
diff --git gcc/testsuite/g++.dg/warn/pr36069.C
gcc/testsuite/g++.dg/warn/pr36069.C
index efb35c25716..7b166351a4b 100644
--- gcc/testsuite/g++.dg/warn/pr36069.C
+++ gcc/testsuite/g++.dg/warn/pr36069.C
@@ -6,11 +6,13 @@ struct foo {
bool a;
volatile bool b,c;
foo() { a = b = c = false; } // { dg-bogus "parentheses" }
+ // { dg-warning "deprecated" "" { target c++2a } .-1 }
};
int main() {
bool a;
volatile bool b,c;
a = b = c = false; // { dg-bogus "parentheses" }
+ // { dg-warning "deprecated" "" { target c++2a } .-1 }
foo A;
}
diff --git gcc/testsuite/g++.old-deja/g++.mike/p9506.C
gcc/testsuite/g++.old-deja/g++.mike/p9506.C
index db16e3738e2..97594640f96 100644
--- gcc/testsuite/g++.old-deja/g++.mike/p9506.C
+++ gcc/testsuite/g++.old-deja/g++.mike/p9506.C
@@ -3,5 +3,5 @@
char * volatile p;
void foo() {
- --p = 0;
+ --p = 0; // { dg-warning "deprecated" "" { target c++2a } }
}
diff --git gcc/testsuite/g++.old-deja/g++.other/volatile1.C
gcc/testsuite/g++.old-deja/g++.other/volatile1.C
index 7d818fbe9e1..a93ef58aa9f 100644
--- gcc/testsuite/g++.old-deja/g++.other/volatile1.C
+++ gcc/testsuite/g++.old-deja/g++.other/volatile1.C
@@ -5,7 +5,7 @@
class f_class // { dg-message "note" "candidates" }
{ };
-volatile f_class
+volatile f_class // { dg-warning "deprecated" "" { target c++2a } }
ret_v_f_class()
{
f_class t;
