2003-04-10 Zack Weinberg <zack@codesourcery.com>

	* c-decl.c (struct binding_level): Add shadowed_tags and
	function_body; remove this_block, tag_transparent, and
	subblocks_tag_transparent; update comments.
	(clear_binding_level, lookup_tag_reverse): Kill.
	(make_binding_level): Use ggc_alloc_cleared or memset.
	(lookup_tag): Remove struct binding_level* parameter.  All
	callers changed. Just look at IDENTIFIER_TAG_VALUE, and
	current_binding_level->tags if asked for thislevel_only or if
	we might have to diagnose "struct foo; union foo;"
	(pushlevel): Ignore argument.  Do not push another binding
	level on the transition from the parameters to the top level
	of the function body; just tweak the flags and proceed.
	(poplevel): Overhaul.  Clear IDENTIFIER_TAG_VALUEs; on exiting
	a function body, separate the parameter list from the
	top-level local variables.
	(set_block): Do nothing.
	(pushtag): Set IDENTIFIER_TAG_VALUE and add an entry to
	shadowed_tags if necessary.
	(warn_if_shadowing): Nuke the special case for local shadowing
	parameter.
	(pushdecl): Do not create a shadow entry if we are replacing
	an older decl in the same binding level.
	(pushdecl_function_level): Tweak for new way of indicating
	function scope.
	(shadow_tag_warned): Use TYPE_NAME, not	lookup_tag_reverse.
	(start_function): Don't set subblocks_tag_transparent.
	(finish_function): Fix up the binding_level stack for totally
	empty functions.  Otherwise, don't call poplevel.

	* c-common.c (shadow_warning): MANDATORY argument is no longer
	necessary.  Always use plain warning.
	* c-common.h: Update to match.

	* cfglayout.c (scope_to_insns_initialize): Clear block when we
	hit the FUNCTION_DECL.
	* function.c: Do not create cyclic tree structure.

2003-04-10  Zack Weinberg  <zack@codesourcery.com>

	* c-tree.h (struct lang_identifier): Replace global_value,
	local_value members with symbol_value, tag_value.  Kill
	implicit_decl and limbo_value.
	(IDENTIFIER_GLOBAL_VALUE, IDENTIFIER_LOCAL_VALUE,
	IDENTIFIER_LIMBO_VALUE, IDENTIFIER_IMPLICIT_DECL,
	C_MISSING_PROTOTYPE_WARNED): Kill.
	(IDENTIFIER_SYMBOL_VALUE, IDENTIFIER_TAG_VALUE,
	C_DECL_IMPLICIT, C_DECL_ISNT_PROTOTYPE): New.
	(C_DECL_ANTICIPATED): Rename to C_DECL_INVISIBLE.
	(implicit_decl_warning, lookup_name_current_level,
	record_function_scope_shadow): Don't prototype.
	(pushdecl_function_level): Prototype.

	* c-decl.c (truly_local_externals): New variable.
	(struct binding_level): Adjust commentary.
	(get_function_binding_level, clear_limbo_values,
	record_function_scope_shadow): Kill.
	(lookup_name_current_level, implicit_decl_warning): Are	now static.
	(any_external_decl, record_external_decl): New static functions.
	(clone_underlying type): Split out of pushdecl.
	(c_print_identifier): Update to match changes to struct
	lang_identifier.
	(poplevel): Delete #if 0 block.  Make externals invisible
	instead of clearing their IDENTIFIER_SYMBOL_VALUEs.  Don't
	call clear_limbo_values.  Refer to IDENTIFIER_SYMBOL_VALUE not
	IDENTIFIER_GLOBAL_VALUE or IDENTIFIER_LOCAL_VALUE.
	(duplicate-decls): For real parm decl after a forward decl,
	set TREE_ASM_WRITTEN here.  Allow void foo(...) followed by
	foo(...) { } with only a warning.  Say whether a previous
	declaration was implicit.
	(warn_if_shadowing): Now handles all shadowing, not just
	local-over-local.  Clarify comments.
	(pushdecl): Rewritten.  There is no longer a distinction
	between global and local symbol values; they're all
	IDENTIFIER_SYMBOL_VALUE.  Call record_external_decl on all
	DECL_EXTERNAL decls, and use any_external_decl to check
	against previous externals.  Kill #if 0 blocks.  Don't
	tolerate error_mark_node being NULL.
	(pushdecl_top_level): Handle only those cases which
	Objective C (the only user) needs.
	(pushdecl_function_level): New function.
	(implicitly_declare): Create ordinary decls with
	C_DECL_IMPLICIT set.  Recycle old decls, however they got
	created.
	(lookup_name): It's always IDENTIFIER_SYMBOL_VALUE. Return 0
	for C_DECL_INVISIBLE symbols.
	(lookup_name_current_level): Likewise.  Use chain_member.
	(c_make_fname_decl): Don't muck with DECL_CONTEXT.
	Use pushdecl_function_level.
	(builtin_function): Use C_DECL_INVISIBLE.
	(start_function): Don't muck with IDENTIFIER_IMPLICIT_DECL.
	Use C_DECL_ISNT_PROTOTYPE and C_DECL_IMPLICIT.
	(store_parm_decls): It's IDENTIFIER_SYMBOL_VALUE now.
	(identifier_global_value): Same.  Must scan
	global_binding_level in extremis.

	* c-typeck.c (undeclared_variable): New static function, split
	from build_external_ref.
	(build_external_ref): Use DECL_CONTEXT, not
	IDENTIFIER_LOCAL_VALUE, to decide whether a local hides
	an instance variable.  Restructure for clarity.
	* objc/objc-act.c: Use identifier_global_value, not
	IDENTIFIER_GLOBAL_VALUE.

cp:
	* decl.c: Update all calls to shadow_warning.

testsuite:
	* gcc.c-torture/execute/builtin-noret-2.c: New.
	* gcc.c-torture/execute/builtin-noret-2.x: New.
	XFAIL builtin-noret-2.c at -O1 and above.
	* gcc.dg/redecl.c: New.
	* gcc.dg/Wshadow-1.c: Update error regexps.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@65460 138bc75d-0d04-0410-961f-82ee72b054a4

5 files changed, 207 insertions, 2 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 52be21cb002..7b23832937e 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2003-04-10  Zack Weinberg  <zack@codesourcery.com>
+
+	* gcc.c-torture/execute/builtin-noret-2.c: New.
+	* gcc.c-torture/execute/builtin-noret-2.x: New.
+	XFAIL builtin-noret-2.c at -O1 and above.
+	* gcc.dg/redecl.c: New.
+	* gcc.dg/Wshadow-1.c: Update error regexps.
+
 2003-04-10  Mark Mitchell  <mark@codesourcery.com>
 
 	* g++.dg/abi/bitfield10.C: New test.
diff --git a/gcc/testsuite/gcc.c-torture/execute/builtin-noret-2.c b/gcc/testsuite/gcc.c-torture/execute/builtin-noret-2.c
new file mode 100644
index 00000000000..077153b1cb9
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/builtin-noret-2.c
@@ -0,0 +1,84 @@
+/* Test for builtin noreturn attributes when the visible declarations
+   are function-local.  Doesn't presently work.  Modified from
+   builtin-noret-1.c by Zack Weinberg <zack@codesourcery.com>.  */
+
+extern void tabort (void);
+extern void texit (void);
+extern void t_exit (void);
+extern void t_Exit (void);
+
+extern void link_failure (void);
+
+int
+main (void)
+{
+  volatile int i = 0;
+  /* The real test here is that the program links.  */
+  if (i)
+    tabort ();
+  if (i)
+    texit ();
+  if (i)
+    t_exit ();
+  if (i)
+    t_Exit ();
+  exit (0);
+}
+
+void
+tabort (void)
+{
+  extern void abort (void);
+  abort ();
+  link_failure ();
+}
+
+void
+texit (void)
+{
+  extern void exit (int);
+  exit (1);
+  link_failure ();
+}
+
+void
+t_exit (void)
+{
+  extern void _exit (int);
+  _exit (1);
+  link_failure ();
+}
+
+/* Some non-Unix libcs might not have _exit.  This version should never
+   get called.  */
+static void
+_exit (int i)
+{
+  abort ();
+}
+
+void
+t_Exit (void)
+{
+  extern void _Exit (int);
+  _Exit (1);
+  link_failure ();
+}
+
+/* Some libcs might not have _Exit.  This version should never get called.  */
+static void
+_Exit (int i)
+{
+  abort ();
+}
+
+/* When optimizing, no calls to link_failure should remain.  In any case,
+   link_failure should not be called.  */
+
+#ifndef __OPTIMIZE__
+void
+link_failure (void)
+{
+  abort ();
+}
+#endif
diff --git a/gcc/testsuite/gcc.c-torture/execute/builtin-noret-2.x b/gcc/testsuite/gcc.c-torture/execute/builtin-noret-2.x
new file mode 100644
index 00000000000..7926a94f781
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/builtin-noret-2.x
@@ -0,0 +1,12 @@
+# This test fails at -O1 and higher.
+set torture_eval_before_compile {
+    global compiler_conditional_xfail_data
+    set compiler_conditional_xfail_data {
+        "Fails at all optimization levels but -O0, see PR10375." \
+        { "*-*-*" } \
+        { "-O*" } \
+        { "-O0" }
+    }
+}
+
+return 0
diff --git a/gcc/testsuite/gcc.dg/Wshadow-1.c b/gcc/testsuite/gcc.dg/Wshadow-1.c
index 320d4f808da..c9c3acb98c9 100644
--- a/gcc/testsuite/gcc.dg/Wshadow-1.c
+++ b/gcc/testsuite/gcc.dg/Wshadow-1.c
@@ -10,10 +10,10 @@ void foo (double decl1)		/* { dg-warning "shadows a global decl" } */
 {				
 }
 
-void foo1 (int d)		/* { dg-warning "shadowed declaration" } */
+void foo1 (int d)		/* { dg-warning "previous declaration" } */
 {
   double d;	 /* { dg-bogus "warning" "warning in place of error" } */
-  /* { dg-error "shadows a parameter" "" { target *-*-* } 15 } */
+  /* { dg-error "redeclared as different" "" { target *-*-* } 15 } */
 }
 
 void foo2 (int d)		/* { dg-warning "shadowed declaration" } */
diff --git a/gcc/testsuite/gcc.dg/redecl-1.c b/gcc/testsuite/gcc.dg/redecl-1.c
new file mode 100644
index 00000000000..d2355ba7aa2
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/redecl-1.c
@@ -0,0 +1,101 @@
+/* Test for various situations where a new declaration of an
+   identifier conflicts with an earlier declaration which isn't in the
+   same scope.  These are all undefined behavior per C89 sections
+   6.1.2.2p7, 6.1.2.6p2, and 6.3.2.2p2/footnote 38 (C99 6.2.2p7 and
+   6.2.7p2 - implicit declarations are invalid in C99).  */
+
+/* { dg-do compile } */
+/* { dg-options "-std=c89 -pedantic -Wall -Wno-unused" } */
+
+/* Extern at function scope, clashing with extern at file scope */
+
+extern int foo1;		/* { dg-error "previous" } */
+extern int bar1(int);		/* { dg-error "previous" } */
+
+void test1(void)
+{
+  extern double foo1;		/* { dg-error "conflict" } */
+  extern double bar1(double);	/* { dg-error "conflict" } */
+}
+
+/* Extern at file scope, clashing with extern at function scope */
+
+void test2(void)
+{
+  extern double foo2;		/* { dg-error "previous" } */
+  extern double bar2(double);	/* { dg-error "previous" } */
+}
+
+extern int foo2;		/* { dg-error "conflict" } */
+extern int bar2(int);		/* { dg-error "conflict" } */
+
+/* Extern at function scope, clashing with extern at earlier function
+   scope.  Also, don't be fooled by a typedef at file scope.  */
+
+typedef float baz3;		/* { dg-bogus } */
+
+void prime3(void)
+{
+  extern int foo3;		/* { dg-error "previous" } */
+  extern int bar3(int);		/* { dg-error "previous" } */
+  extern int baz3;		/* { dg-error "previous" } */
+}
+
+void test3(void)
+{
+  extern double foo3;		/* { dg-error "conflict" } */
+  extern double bar3(double);	/* { dg-error "conflict" } */
+  extern double baz3;		/* { dg-error "conflict" } */
+}
+
+/* Extern at function scope, clashing with previous implicit decl.  */
+
+void prime4(void)
+{
+  bar4();			/* { dg-error "previous|implicit" } */
+}
+
+void test4(void)
+{
+  extern double bar4(double);	/* { dg-error "conflict" } */
+}
+
+/* Implicit decl, clashing with extern at previous function scope.  */
+
+void prime5(void)
+{
+  extern double bar5(double);	/* { dg-error "previous" "" { xfail *-*-* } } */
+}
+
+void test5(void)
+{
+  bar5(1);			/* { dg-error "implicit" } */
+}
+
+/* Extern then static, both at file scope.  */
+
+extern int test6(int);		/* { dg-warning "previous" "" { xfail *-*-* } } */
+static int test6(int x)			
+{ return x; }			/* { dg-warning "follows non-static" } */
+
+
+/* Extern then static, extern at previous function scope.  */
+
+void prime7(void)
+{
+  extern int test7(int);	/* { dg-warning "previous" "" { xfail *-*-* } } */
+}
+
+static int test7(int x)
+{ return x; }			/* { dg-warning "follows non-static" } */
+
+/* Implicit decl then static.  */
+
+void prime8(void)
+{
+  test8();			/* { dg-warning "previous" "" { xfail *-*-* } } */
+                                /* { dg-warning "implicit" "" { target *-*-* } 96 } */
+}
+
+static int test8(int x)
+{ return x; }			/* { dg-warning "follows non-static" } */