This patch adds a new warning option: Wswitch-outside-range, so that
users are able to selectively control the warning. The warning is
enabled by default.
Best,
Matthew Beliveau
Bootstrapped/regtested on x86_64-linux, ok for trunk?
2019-06-14 Matthew Beliveau <mbeli...@redhat.com>
PR c++/90875 - added -Wswitch-outside-range option
* doc/invoke.texi (Wswitch-outside-range): Document.
* c-warn.c (c_do_switch_warnings): Implemented new Wswitch-outside-range
warning option.
* c.opt (Wswitch-outside-range): Added new option.
* g++.dg/warn/Wswitch-outside-range-1.C: New test.
* g++.dg/warn/Wswitch-outside-range-2.C: New test.
* g++.dg/warn/Wswitch-outside-range-3.C: New test.
* g++.dg/warn/Wswitch-outside-range-4.C: New test.
diff --git gcc/c-family/c-warn.c gcc/c-family/c-warn.c
index 5941c10cddb..b61694af638 100644
--- gcc/c-family/c-warn.c
+++ gcc/c-family/c-warn.c
@@ -1460,8 +1460,9 @@ c_do_switch_warnings (splay_tree cases, location_t switch_location,
min_value) >= 0)
{
location_t loc = EXPR_LOCATION ((tree) node->value);
- warning_at (loc, 0, "lower value in case label range"
- " less than minimum value for type");
+ warning_at (loc, OPT_Wswitch_outside_range, "lower value in case"
+ " label range less than minimum value"
+ " for type");
CASE_LOW ((tree) node->value) = convert (TREE_TYPE (cond),
min_value);
node->key = (splay_tree_key) CASE_LOW ((tree) node->value);
@@ -1474,8 +1475,8 @@ c_do_switch_warnings (splay_tree cases, location_t switch_location,
if (node == NULL || !node->key)
break;
location_t loc = EXPR_LOCATION ((tree) node->value);
- warning_at (loc, 0, "case label value is less than minimum "
- "value for type");
+ warning_at (loc, OPT_Wswitch_outside_range, "case label value is"
+ " less than minimum value for type");
splay_tree_remove (cases, node->key);
}
while (1);
@@ -1491,8 +1492,8 @@ c_do_switch_warnings (splay_tree cases, location_t switch_location,
max_value) > 0)
{
location_t loc = EXPR_LOCATION ((tree) node->value);
- warning_at (loc, 0, "upper value in case label range"
- " exceeds maximum value for type");
+ warning_at (loc, OPT_Wswitch_outside_range, "upper value in case"
+ " label range exceeds maximum value for type");
CASE_HIGH ((tree) node->value)
= convert (TREE_TYPE (cond), max_value);
outside_range_p = true;
@@ -1503,7 +1504,7 @@ c_do_switch_warnings (splay_tree cases, location_t switch_location,
!= NULL)
{
location_t loc = EXPR_LOCATION ((tree) node->value);
- warning_at (loc, 0,
+ warning_at (loc, OPT_Wswitch_outside_range,
"case label value exceeds maximum value for type");
splay_tree_remove (cases, node->key);
outside_range_p = true;
diff --git gcc/c-family/c.opt gcc/c-family/c.opt
index 572cf186262..4ced767ca99 100644
--- gcc/c-family/c.opt
+++ gcc/c-family/c.opt
@@ -819,6 +819,10 @@ Wswitch-bool
C ObjC C++ ObjC++ Var(warn_switch_bool) Warning Init(1)
Warn about switches with boolean controlling expression.
+Wswitch-outside-range
+C++ ObjC++ Var(warn_switch_outside_range) Warning Init(1)
+Warn about switch values that are outside of their type's range.
+
Wtemplates
C++ ObjC++ Var(warn_templates) Warning
Warn on primary template declaration.
diff --git gcc/doc/invoke.texi gcc/doc/invoke.texi
index bf9da0f0a6e..c23496b2668 100644
--- gcc/doc/invoke.texi
+++ gcc/doc/invoke.texi
@@ -5390,6 +5390,12 @@ switch ((int) (a == 4))
@end smallexample
This warning is enabled by default for C and C++ programs.
+@item -Wswitch-outside-range
+@opindex Wswitch-outside-range
+@opindex Wno-switch-outside-range
+Warn whenever a @code{switch} state has a value that is outside of it's
+respective type range.
+
@item -Wswitch-unreachable
@opindex Wswitch-unreachable
@opindex Wno-switch-unreachable
diff --git gcc/testsuite/g++.dg/warn/Wswitch-outside-range-1.C gcc/testsuite/g++.dg/warn/Wswitch-outside-range-1.C
new file mode 100644
index 00000000000..29e56f3ba2d
--- /dev/null
+++ gcc/testsuite/g++.dg/warn/Wswitch-outside-range-1.C
@@ -0,0 +1,8 @@
+// PR c++/90875
+
+void f(char c)
+{
+ switch (c)
+ case 300: // { dg-warning "case label value exceeds maximum value for type" }
+ case -300:; // { dg-warning "case label value is less than minimum value for type" }
+}
diff --git gcc/testsuite/g++.dg/warn/Wswitch-outside-range-2.C gcc/testsuite/g++.dg/warn/Wswitch-outside-range-2.C
new file mode 100644
index 00000000000..20cc019b209
--- /dev/null
+++ gcc/testsuite/g++.dg/warn/Wswitch-outside-range-2.C
@@ -0,0 +1,9 @@
+// PR c++/90875
+// { dg-options -Wno-switch-outside-range }
+
+void f(char c)
+{
+ switch (c)
+ case 300: //{ dg-bogus "case label value is less than minimum value for type" }
+ case -300:; // { dg-bogus "case label value is less than minimum value for type" }
+}
diff --git gcc/testsuite/g++.dg/warn/Wswitch-outside-range-3.C gcc/testsuite/g++.dg/warn/Wswitch-outside-range-3.C
new file mode 100644
index 00000000000..baf15561af0
--- /dev/null
+++ gcc/testsuite/g++.dg/warn/Wswitch-outside-range-3.C
@@ -0,0 +1,9 @@
+// PR c++/90875
+// { dg-options -Wno-pedantic }
+
+void f(char c)
+{
+ switch (c)
+
+ case -300 ... 300:; // { dg-warning "lower value in case label range less than minimum value for type|upper value in case label range exceeds maximum value for type" }
+}
diff --git gcc/testsuite/g++.dg/warn/Wswitch-outside-range-4.C gcc/testsuite/g++.dg/warn/Wswitch-outside-range-4.C
new file mode 100644
index 00000000000..d9bd756dc50
--- /dev/null
+++ gcc/testsuite/g++.dg/warn/Wswitch-outside-range-4.C
@@ -0,0 +1,9 @@
+// PR c++/90875
+// { dg-options "-Wno-pedantic -Wno-switch-outside-range" }
+
+void f(char c)
+{
+ switch (c)
+
+ case -300 ... 300:; // { dg-bogus "lower value in case label range less than minimum value for type|upper value in case label range exceeds maximum value for type" }
+}
