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

2007-01-02  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>

	PR middle-end/7651
	* c.opt (Wold-style-declaration): New.
	* doc/invoke.texi (C-only Warning Options): New.
	(Wold-style-declaration): Document it.
	(Wextra): Enabled by -Wextra.
	* c-opts.c (c_common_post_options): Enabled by -Wextra.
	* c-decl.c (declspecs_add_scspec): Replace -Wextra with
	-Wold-style-declaration.

testsuite/
	* gcc.dg/declspec-3.c: Replace -W with -Wold-style-declaration.
	* gcc.dg/declspec-3-Wextra.c: New.
	* gcc.dg/declspec-3-no.c: New

From-SVN: r120347

9 files changed, 108 insertions, 9 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6b3103e..78b8ce8 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2007-01-02  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+	PR middle-end/7651
+	* c.opt (Wold-style-declaration): New.
+	* doc/invoke.texi (C-only Warning Options): New.
+	(Wold-style-declaration): Document it.
+	(Wextra): Enabled by -Wextra.
+	* c-opts.c (c_common_post_options): Enabled by -Wextra.
+	* c-decl.c (declspecs_add_scspec): Replace -Wextra with
+	-Wold-style-declaration.
+	
 2007-01-02  Kazu Hirata  <kazu@codesourcery.com>
 
 	* alias.c (init_alias_analysis): Use VEC_safe_grow_cleared.
diff --git a/gcc/c-decl.c b/gcc/c-decl.c
index a9506e1..f669a47 100644
--- a/gcc/c-decl.c
+++ b/gcc/c-decl.c
@@ -7613,8 +7613,9 @@ declspecs_add_scspec (struct c_declspecs *specs, tree scspec)
   gcc_assert (TREE_CODE (scspec) == IDENTIFIER_NODE
 	      && C_IS_RESERVED_WORD (scspec));
   i = C_RID_CODE (scspec);
-  if (extra_warnings && specs->non_sc_seen_p)
-    warning (OPT_Wextra, "%qE is not at beginning of declaration", scspec);
+  if (specs->non_sc_seen_p)
+    warning (OPT_Wold_style_declaration, 
+             "%qE is not at beginning of declaration", scspec);
   switch (i)
     {
     case RID_INLINE:
diff --git a/gcc/c-opts.c b/gcc/c-opts.c
index 5390a05..acba12b 100644
--- a/gcc/c-opts.c
+++ b/gcc/c-opts.c
@@ -1026,7 +1026,8 @@ c_common_post_options (const char **pfilename)
     flag_exceptions = 1;
 
   /* -Wextra implies -Wclobbered, -Wempty-body, -Wsign-compare, 
-     -Wmissing-field-initializers, -Wmissing-parameter-type and -Woverride-init, 
+     -Wmissing-field-initializers, -Wmissing-parameter-type
+     -Wold-style-declaration, and -Woverride-init, 
      but not if explicitly overridden.  */
   if (warn_clobbered == -1)
     warn_clobbered = extra_warnings;
@@ -1038,6 +1039,8 @@ c_common_post_options (const char **pfilename)
     warn_missing_field_initializers = extra_warnings;
   if (warn_missing_parameter_type == -1)
     warn_missing_parameter_type = extra_warnings;
+  if (warn_old_style_declaration == -1)
+    warn_old_style_declaration = extra_warnings;
   if (warn_override_init == -1)
     warn_override_init = extra_warnings;
 
diff --git a/gcc/c.opt b/gcc/c.opt
index e4d45e4..5500d08 100644
--- a/gcc/c.opt
+++ b/gcc/c.opt
@@ -319,6 +319,10 @@ Wold-style-cast
 C++ ObjC++ Var(warn_old_style_cast)
 Warn if a C-style cast is used in a program
 
+Wold-style-declaration
+C ObjC Var(warn_old_style_declaration) Init(-1)
+Warn for obsolescent usage in a declaration
+
 Wold-style-definition
 C ObjC Var(warn_old_style_definition)
 Warn if an old-style parameter definition is used
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index ff463c7..2101192 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -256,8 +256,8 @@ Objective-C and Objective-C++ Dialects}.
 
 @item C-only Warning Options
 @gccoptlist{-Wbad-function-cast  -Wmissing-declarations @gol
--Wmissing-parameter-type  -Wmissing-prototypes @gol
--Wnested-externs  -Wold-style-definition @gol
+-Wmissing-parameter-type  -Wmissing-prototypes  -Wnested-externs @gol
+-Wold-style-declaration  -Wold-style-definition @gol
 -Wstrict-prototypes  -Wtraditional  -Wtraditional-conversion @gol
 -Wdeclaration-after-statement -Wpointer-sign}
 
@@ -2885,9 +2885,11 @@ but @samp{x[(void)i,j]} will not.
 @item
 An unsigned value is compared against zero with @samp{<} or @samp{>=}.
 
-@item
-Storage-class specifiers like @code{static} are not the first things in
-a declaration.  According to the C Standard, this usage is obsolescent.
+@item @r{(C only)}
+Storage-class specifiers like @code{static} are not the first things
+in a declaration.  According to the C Standard, this usage is
+obsolescent.  This warning can be independently controlled by
+@option{-Wold-style-declaration}.
 
 @item
 If @option{-Wall} or @option{-Wunused} is also specified, warn about unused
@@ -3214,6 +3216,13 @@ argument types.  (An old-style function definition is permitted without
 a warning if preceded by a declaration which specifies the argument
 types.)
 
+@item -Wold-style-declaration @r{(C only)}
+@opindex Wold-style-declaration
+Warn for obsolescent usages, according to the C Standard, in a
+declaration. For example, warn if storage-class specifiers like
+@code{static} are not the first things in a declaration.  This warning
+is also enabled by @option{-Wextra}.
+
 @item -Wold-style-definition @r{(C only)}
 @opindex Wold-style-definition
 Warn if an old-style function definition is used.  A warning is given
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 81ac58c..e2e3d3d 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2007-01-02  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+	PR middle-end/7651
+	* gcc.dg/declspec-3.c: Replace -W with -Wold-style-declaration.
+	* gcc.dg/declspec-3-Wextra.c: New.
+	* gcc.dg/declspec-3-no.c: New
+
 2007-01-02  Paul Thomas  <pault@gcc.gnu.org>
 
 	PR fortran/20896
diff --git a/gcc/testsuite/gcc.dg/declspec-3-Wextra.c b/gcc/testsuite/gcc.dg/declspec-3-Wextra.c
new file mode 100644
index 0000000..66378cc
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/declspec-3-Wextra.c
@@ -0,0 +1,32 @@
+/* See declspec-3.c . Test -Wold-style-declaration is enabled by -Wextra. */
+/* { dg-do compile } */
+/* { dg-options "-Wextra" } */
+
+static int x0;
+int static x1; /* { dg-warning "not at beginning" } */
+
+extern int x2;
+int extern x3; /* { dg-warning "not at beginning" } */
+
+typedef int x4;
+int typedef x5; /* { dg-warning "not at beginning" } */
+
+void g (int);
+
+void
+f (void)
+{
+  auto int x6 = 0;
+  int auto x7 = 0; /* { dg-warning "not at beginning" } */
+  register int x8 = 0;
+  int register x9 = 0; /* { dg-warning "not at beginning" } */
+  g (x6 + x7 + x8 + x9);
+}
+
+const static int x10; /* { dg-warning "not at beginning" } */
+
+/* Attributes are OK before storage class specifiers, since some
+   attributes are like such specifiers themselves.  */
+
+__attribute__((format(printf, 1, 2))) static void h (const char *, ...);
+__attribute__((format(printf, 1, 2))) void static i (const char *, ...); /* { dg-warning "not at beginning" } */
diff --git a/gcc/testsuite/gcc.dg/declspec-3-no.c b/gcc/testsuite/gcc.dg/declspec-3-no.c
new file mode 100644
index 0000000..678b4f2
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/declspec-3-no.c
@@ -0,0 +1,32 @@
+/* See declspec-3.c . Test disabling -Wold-style-declaration. */
+/* { dg-do compile } */
+/* { dg-options "-Wextra -Wno-old-style-declaration" } */
+
+static int x0;
+int static x1; /* { dg-bogus "not at beginning" } */
+
+extern int x2;
+int extern x3; /* { dg-bogus "not at beginning" } */
+
+typedef int x4;
+int typedef x5; /* { dg-bogus "not at beginning" } */
+
+void g (int);
+
+void
+f (void)
+{
+  auto int x6 = 0;
+  int auto x7 = 0; /* { dg-bogus "not at beginning" } */
+  register int x8 = 0;
+  int register x9 = 0; /* { dg-bogus "not at beginning" } */
+  g (x6 + x7 + x8 + x9);
+}
+
+const static int x10; /* { dg-bogus "not at beginning" } */
+
+/* Attributes are OK before storage class specifiers, since some
+   attributes are like such specifiers themselves.  */
+
+__attribute__((format(printf, 1, 2))) static void h (const char *, ...);
+__attribute__((format(printf, 1, 2))) void static i (const char *, ...); /* { dg-bogus "not at beginning" } */
diff --git a/gcc/testsuite/gcc.dg/declspec-3.c b/gcc/testsuite/gcc.dg/declspec-3.c
index 19b1fa2..95052a9 100644
--- a/gcc/testsuite/gcc.dg/declspec-3.c
+++ b/gcc/testsuite/gcc.dg/declspec-3.c
@@ -2,7 +2,7 @@
    specifiers not at start.  */
 /* Origin: Joseph Myers <jsm@polyomino.org.uk> */
 /* { dg-do compile } */
-/* { dg-options "-W" } */
+/* { dg-options "-Wold-style-declaration" } */
 
 static int x0;
 int static x1; /* { dg-warning "not at beginning" } */