re PR middle-end/7651 (Define -Wextra strictly in terms of other warning flags)

2006-12-22  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>

	PR middle-end/7651
	* c.opt (Wclobbered): New.
	* doc/invoke.texi (Wclobbered): Document it.
	(Wextra): Enabled by -Wextra.
	* c-opts.c (c_common_post_options): Enabled by -Wextra.
	* flow.c (rest_of_handle_life): Replace Wextra with Wclobbered.
	* function.c (setjmp_vars_warning): Only warn for Wclobbered.
	(setjmp_args_warning): Likewise.

testsuite/

	* gcc.dg/attr-returns_twice-1.c: Replace Wextra with Wclobbered.
	* gcc.dg/setjmp-1.c: Add explicit Wclobbered.

From-SVN: r120151

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 212d0ca1aab6168b3a18b787e2bac1843edb135a..4ceb90faa399836ca895340e6afd5e295d4af9c6 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2006-12-22  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+       PR middle-end/7651
+       * c.opt (Wclobbered): New.
+       * doc/invoke.texi (Wclobbered): Document it.
+       (Wextra): Enabled by -Wextra.
+       * c-opts.c (c_common_post_options): Enabled by -Wextra.
+       * flow.c (rest_of_handle_life): Replace Wextra with Wclobbered.
+       * function.c (setjmp_vars_warning): Only warn for Wclobbered.
+       (setjmp_args_warning): Likewise.
+       
 2006-12-22  Kazu Hirata  <kazu@codesourcery.com>
 
        * config/elfos.h, config/spu/spu.c, tree-ssa-operands.h,

diff --git a/gcc/c-opts.c b/gcc/c-opts.c
index 9a5d6f6ca3a38061a90fdb6aa899140e51be7af8..12caf1bb949950f9a759fd26d807ac80a36b0fae 100644 (file)
--- a/gcc/c-opts.c
+++ b/gcc/c-opts.c
@@ -1025,9 +1025,11 @@ c_common_post_options (const char **pfilename)
   if (flag_objc_exceptions && !flag_objc_sjlj_exceptions)
     flag_exceptions = 1;
 
-  /* -Wextra implies -Wempty-body, -Wsign-compare, 
+  /* -Wextra implies -Wclobbered, -Wempty-body, -Wsign-compare, 
      -Wmissing-field-initializers and -Woverride-init, 
      but not if explicitly overridden.  */
+  if (warn_clobbered == -1)
+    warn_clobbered = extra_warnings;
   if (warn_empty_body == -1)
     warn_empty_body = extra_warnings;
   if (warn_sign_compare == -1)

diff --git a/gcc/c.opt b/gcc/c.opt
index 7914b6d6ef0b3edfe608391f960e34c0a6dea95b..74aef8e0303b6cb09d08a6ea2dff33b0322f0797 100644 (file)
--- a/gcc/c.opt
+++ b/gcc/c.opt
@@ -141,6 +141,10 @@ Wchar-subscripts
 C ObjC C++ ObjC++ Var(warn_char_subscripts)
 Warn about subscripts whose type is \"char\"
 
+Wclobbered
+C ObjC C++ ObjC++ Var(warn_clobbered) Init(-1)
+Warn about variables that might be changed by \"longjmp\" or \"vfork\"
+
 Wcomment
 C ObjC C++ ObjC++
 Warn about possibly nested block comments, and C++ comments spanning more than one physical line

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 1c3c9dfba46e978e4fd7127a92c7eabb2d5e5de8..b65280bfce0b465cd0c283b4dbdb3b22ec913faf 100644 (file)
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -222,7 +222,8 @@ Objective-C and Objective-C++ Dialects}.
 @xref{Warning Options,,Options to Request or Suppress Warnings}.
 @gccoptlist{-fsyntax-only  -pedantic  -pedantic-errors @gol
 -w  -Wextra  -Wall  -Waggregate-return -Walways-true -Wno-attributes @gol
--Wc++-compat -Wcast-align  -Wcast-qual  -Wchar-subscripts  -Wcomment @gol
+-Wc++-compat -Wcast-align  -Wcast-qual  -Wchar-subscripts @gol
+-Wclobbered  -Wcomment @gol
 -Wconversion  -Wno-deprecated-declarations @gol
 -Wdisabled-optimization  -Wno-div-by-zero  @gol
 -Wempty-body  -Wno-endif-labels @gol
@@ -2925,6 +2926,7 @@ A pointer is compared against integer zero with @samp{<}, @samp{<=},
 
 @item
 A variable might be changed by @samp{longjmp} or @samp{vfork}.
+This warning can be independently controlled by @option{-Wclobbered}.
 
 @item
 Any of several floating-point events that often indicate errors, such as
@@ -3157,6 +3159,11 @@ only if you have been very careful about using @code{const} in
 declarations and prototypes.  Otherwise, it will just be a nuisance;
 this is why we did not make @option{-Wall} request these warnings.
 
+@item -Wclobbered
+@opindex Wclobbered
+Warn for variables that might be changed by @samp{longjmp} or
+@samp{vfork}.  This warning is also enabled by @option{-Wextra}.
+
 @item -Wconversion
 @opindex Wconversion
 Warn for implicit conversions that may alter a value. This includes

diff --git a/gcc/flow.c b/gcc/flow.c
index 1da935bda31d9b92cc3be11c83806abc536e2116..78c23281c6b25c4d4c5a8b9dea4ed274b11fd689 100644 (file)
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -4695,7 +4695,7 @@ rest_of_handle_life (void)
     cleanup_cfg (CLEANUP_EXPENSIVE | CLEANUP_UPDATE_LIFE | CLEANUP_LOG_LINKS
                  | (flag_thread_jumps ? CLEANUP_THREADING : 0));
 
-  if (extra_warnings)
+  if (warn_clobbered)
     {
       setjmp_vars_warning (DECL_INITIAL (current_function_decl));
       setjmp_args_warning ();

diff --git a/gcc/function.c b/gcc/function.c
index b61b9004a78cbc60dbbb1db1cf9123788d711299..581c0834d44c5b0741166f7f2722a2d6c2e9a6b4 100644 (file)
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -3536,9 +3536,8 @@ setjmp_vars_warning (tree block)
          && DECL_RTL_SET_P (decl)
          && REG_P (DECL_RTL (decl))
          && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
-       warning (0, "variable %q+D might be clobbered by %<longjmp%>"
-                " or %<vfork%>",
-                decl);
+       warning (OPT_Wclobbered, "variable %q+D might be clobbered by" 
+                 " %<longjmp%> or %<vfork%>", decl);
     }
 
   for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
@@ -3557,7 +3556,8 @@ setjmp_args_warning (void)
     if (DECL_RTL (decl) != 0
        && REG_P (DECL_RTL (decl))
        && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
-      warning (0, "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
+      warning (OPT_Wclobbered, 
+               "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
               decl);
 }
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f49fa37e2e9bd1f944f0fae1288aad3e926ea45c..5fc63cfc4357f98ac989011bc40a8d45adb13220 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2006-12-22  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+       PR middle-end/7651
+       * gcc.dg/attr-returns_twice-1.c: Replace Wextra with Wclobbered.
+       * gcc.dg/setjmp-1.c: Add explicit Wclobbered.
+
 2006-12-21  Andrew Pinski  <pinskia@gmail.com>
 
        PR C++/30168

diff --git a/gcc/testsuite/gcc.dg/attr-returns_twice-1.c b/gcc/testsuite/gcc.dg/attr-returns_twice-1.c
index 9eb082f4b0363023449ee51fb7810b53f6c9aec3..e2e725e36345801905055c7216a53456cb506f52 100644 (file)
--- a/gcc/testsuite/gcc.dg/attr-returns_twice-1.c
+++ b/gcc/testsuite/gcc.dg/attr-returns_twice-1.c
@@ -1,5 +1,5 @@
 /* { dg-do compile { target i?86-*-* x86_64-*-* } } */
-/* { dg-options "-W" } */
+/* { dg-options "-Wclobbered" } */
 
 int newsetjmp(void) __attribute__((returns_twice));
 void g(int);

diff --git a/gcc/testsuite/gcc.dg/setjmp-1.c b/gcc/testsuite/gcc.dg/setjmp-1.c
index 35e192de0c966b25aa0cdcdc9a098fc7480787d1..b5c84fc8792da3418bff517d5dc8aa7e112fc392 100644 (file)
--- a/gcc/testsuite/gcc.dg/setjmp-1.c
+++ b/gcc/testsuite/gcc.dg/setjmp-1.c
@@ -2,7 +2,7 @@
    Inspired by cse.c:simplify_relational_operation. */
 
 /* { dg-do compile } */
-/* { dg-options "-O -W -Wall" } */
+/* { dg-options "-O -Wclobbered -Wextra -Wall" } */
 
 #include <setjmp.h>