On 05/06/2014 20:01, Joseph S. Myers wrote:
>
>> Initially, I implemented -Wmissing-return to manage this case (
>> https://gcc.gnu.org/ml/gcc-patches/2014-01/msg00820.html ) but Jason
>> suggested to remove that:
>> https://gcc.gnu.org/ml/gcc-patches/2014-01/msg01033.html
>> (I don't have a strong opinion on the subject).
> I think splitting the option like that makes sense. Compatibility
> indicates that -Wreturn-type and -Wall should still enable
> -Wmissing-return, but only the other pieces of -Wreturn-type should be
> enabled by default, at least for C. (Enabling -Wimplicit-int by default
> might be a good starting point.)
OK.
As attachment, you will find a potential implementation. Is that what
you expect?
> Also, at least one testsuite change in your patch is wrong.
OK. Thanks. I've probably made other (I update +1300 of them)
Thanks
Sylvestre
>From 1b936c618c58dc0e899fa9f56013de48f7e4dcd6 Mon Sep 17 00:00:00 2001
From: Sylvestre Ledru <sylves...@debian.org>
Date: Tue, 17 Jun 2014 18:48:29 +0200
Subject: [PATCH 2/2] Enable Wimplicit by default
---
gcc/c-family/c.opt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 050d400..9b9ede7 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -460,7 +460,7 @@ C ObjC Var(warn_implicit_function_declaration) Init(-1) Warning LangEnabledBy(C
Warn about implicit function declarations
Wimplicit-int
-C ObjC Var(warn_implicit_int) Warning LangEnabledBy(C ObjC,Wimplicit)
+C ObjC Var(warn_implicit_int) Warning
Warn when a declaration does not specify a type
Wimport
--
2.0.0
>From 80cd3dff34f74058ab66b69e0e01a05eaf686338 Mon Sep 17 00:00:00 2001
From: Sylvestre Ledru <sylves...@debian.org>
Date: Tue, 17 Jun 2014 18:48:12 +0200
Subject: [PATCH 1/2] Introduce -Wmissing-return (Was part of -Wreturn-type
which is now enabled by default)
---
gcc/c-family/c.opt | 4 ++++
gcc/doc/invoke.texi | 10 +++++++++-
gcc/fortran/options.c | 4 ++++
gcc/tree-cfg.c | 4 ++--
4 files changed, 19 insertions(+), 3 deletions(-)
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 91f8275..050d400 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -697,6 +697,10 @@ Wreturn-type
C ObjC C++ ObjC++ Var(warn_return_type) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++)
+Wmissing-return
+C ObjC C++ ObjC++ Var(warn_missing_return) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
+Warn whenever control may reach end of non-void function
+
Wselector
ObjC ObjC++ Var(warn_selector) Warning
Warn if a selector has multiple methods
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 9a34f1c..9911e86 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -258,7 +258,7 @@ Objective-C and Objective-C++ Dialects}.
-Winvalid-pch -Wlarger-than=@var{len} -Wunsafe-loop-optimizations @gol
-Wlogical-op -Wlogical-not-parentheses -Wlong-long @gol
-Wmain -Wmaybe-uninitialized -Wmissing-braces -Wmissing-field-initializers @gol
--Wmissing-include-dirs @gol
+-Wmissing-include-dirs -Wmissing-return @gol
-Wno-multichar -Wnonnull -Wno-overflow -Wopenmp-simd @gol
-Woverlength-strings -Wpacked -Wpacked-bitfield-compat -Wpadded @gol
-Wparentheses -Wpedantic-ms-format -Wno-pedantic-ms-format @gol
@@ -3327,6 +3327,7 @@ Options} and @ref{Objective-C and Objective-C++ Dialect Options}.
-Wmain @r{(only for C/ObjC and unless} @option{-ffreestanding}@r{)} @gol
-Wmaybe-uninitialized @gol
-Wmissing-braces @r{(only for C/ObjC)} @gol
+-Wmissing-return @gol
-Wnonnull @gol
-Wopenmp-simd @gol
-Wparentheses @gol
@@ -3657,6 +3658,13 @@ the following example, the initializer for @samp{a} is not fully
bracketed, but that for @samp{b} is fully bracketed. This warning is
enabled by @option{-Wall} in C.
+@item -Wmissing-return
+@opindex Wmissing-return
+@opindex Wno-missing-return
+Warn whenever falling off the end of the function body (I.e. without
+any return).
+This warning is enabled by @option{-Wall} for C and C++.
+
@smallexample
int a[2][2] = @{ 0, 1, 2, 3 @};
int b[2][2] = @{ @{ 0, 1 @}, @{ 2, 3 @} @};
diff --git a/gcc/fortran/options.c b/gcc/fortran/options.c
index a2b91ca..fe71230 100644
--- a/gcc/fortran/options.c
+++ b/gcc/fortran/options.c
@@ -698,6 +698,10 @@ gfc_handle_option (size_t scode, const char *arg, int value,
gfc_option.warn_line_truncation = value;
break;
+ case OPT_Wmissing_return:
+ warn_missing_return = value;
+ break;
+
case OPT_Wrealloc_lhs:
gfc_option.warn_realloc_lhs = value;
break;
diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c
index e824619..2fd342e 100644
--- a/gcc/tree-cfg.c
+++ b/gcc/tree-cfg.c
@@ -8265,7 +8265,7 @@ pass_warn_function_return::execute (function *fun)
/* If we see "return;" in some basic block, then we do reach the end
without returning a value. */
- else if (warn_return_type
+ else if (warn_missing_return
&& !TREE_NO_WARNING (fun->decl)
&& EDGE_COUNT (EXIT_BLOCK_PTR_FOR_FN (fun)->preds) > 0
&& !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (fun->decl))))
@@ -8280,7 +8280,7 @@ pass_warn_function_return::execute (function *fun)
location = gimple_location (last);
if (location == UNKNOWN_LOCATION)
location = fun->function_end_locus;
- warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
+ warning_at (location, OPT_Wmissing_return, "control reaches end of non-void function");
TREE_NO_WARNING (fun->decl) = 1;
break;
}
--
2.0.0
