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2010-07-12 Yao Qi <yao@codesourcery.com>
Merge from Sourcery G++ 4.4:
2009-10-06 Paul Brook <paul@codesourcery.com>
Issue #3869
gcc/
* target.h (gcc_target): Add warn_func_result.
* target-def.h (TARGET_WARN_FUNC_RESULT): Define and use.
* tree-cfg.h (execute_warn_function_return): Use
targetm.warn_func_result.
* config/arm/arm.c (TARGET_WARN_FUNC_RESULT): Define.
(arm_warn_func_result): New function.
gcc/testuite/
* gcc.target/arm/naked-3.c: New test.
2010-07-10 Sandra Loosemore <sandra@codesourcery.com>
Backport from mainline:
=== modified file 'gcc/config/arm/arm.c'
--- old/gcc/config/arm/arm.c 2010-07-29 16:58:56 +0000
+++ new/gcc/config/arm/arm.c 2010-07-30 13:58:02 +0000
@@ -214,6 +214,7 @@
static int arm_issue_rate (void);
static void arm_output_dwarf_dtprel (FILE *, int, rtx) ATTRIBUTE_UNUSED;
static bool arm_allocate_stack_slots_for_args (void);
+static bool arm_warn_func_result (void);
static const char *arm_invalid_parameter_type (const_tree t);
static const char *arm_invalid_return_type (const_tree t);
static tree arm_promoted_type (const_tree t);
@@ -378,6 +379,9 @@
#undef TARGET_TRAMPOLINE_ADJUST_ADDRESS
#define TARGET_TRAMPOLINE_ADJUST_ADDRESS arm_trampoline_adjust_address
+#undef TARGET_WARN_FUNC_RESULT
+#define TARGET_WARN_FUNC_RESULT arm_warn_func_result
+
#undef TARGET_DEFAULT_SHORT_ENUMS
#define TARGET_DEFAULT_SHORT_ENUMS arm_default_short_enums
@@ -2008,6 +2012,14 @@
return !IS_NAKED (arm_current_func_type ());
}
+static bool
+arm_warn_func_result (void)
+{
+ /* Naked functions are implemented entirely in assembly, including the
+ return sequence, so suppress warnings about this. */
+ return !IS_NAKED (arm_current_func_type ());
+}
+
/* Output assembler code for a block containing the constant parts
of a trampoline, leaving space for the variable parts.
=== modified file 'gcc/target-def.h'
--- old/gcc/target-def.h 2010-03-24 20:44:48 +0000
+++ new/gcc/target-def.h 2010-07-30 13:58:02 +0000
@@ -212,6 +212,10 @@
#define TARGET_EXTRA_LIVE_ON_ENTRY hook_void_bitmap
#endif
+#ifndef TARGET_WARN_FUNC_RESULT
+#define TARGET_WARN_FUNC_RESULT hook_bool_void_true
+#endif
+
#ifndef TARGET_ASM_FILE_START_APP_OFF
#define TARGET_ASM_FILE_START_APP_OFF false
#endif
@@ -1020,6 +1024,7 @@
TARGET_EMUTLS, \
TARGET_OPTION_HOOKS, \
TARGET_EXTRA_LIVE_ON_ENTRY, \
+ TARGET_WARN_FUNC_RESULT, \
TARGET_UNWIND_TABLES_DEFAULT, \
TARGET_HAVE_NAMED_SECTIONS, \
TARGET_HAVE_SWITCHABLE_BSS_SECTIONS, \
=== modified file 'gcc/target.h'
--- old/gcc/target.h 2010-03-27 10:27:39 +0000
+++ new/gcc/target.h 2010-07-30 13:58:02 +0000
@@ -1171,6 +1171,10 @@
bits in the bitmap passed in. */
void (*live_on_entry) (bitmap);
+ /* Return false if warnings about missing return statements or suspect
+ noreturn attributes should be suppressed for the current function. */
+ bool (*warn_func_result) (void);
+
/* True if unwinding tables should be generated by default. */
bool unwind_tables_default;
=== added file 'gcc/testsuite/gcc.target/arm/naked-3.c'
--- old/gcc/testsuite/gcc.target/arm/naked-3.c 1970-01-01 00:00:00 +0000
+++ new/gcc/testsuite/gcc.target/arm/naked-3.c 2010-07-30 13:58:02 +0000
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -Wall" } */
+/* Check that we do not get warnings about missing return statements
+ or bogus looking noreturn functions. */
+int __attribute__((naked))
+foo(void)
+{
+ __asm__ volatile ("mov r0, #1\r\nbx lr\n");
+}
+
+int __attribute__((naked,noreturn))
+bar(void)
+{
+ __asm__ volatile ("frob r0\n");
+}
=== modified file 'gcc/tree-cfg.c'
--- old/gcc/tree-cfg.c 2010-03-16 12:31:38 +0000
+++ new/gcc/tree-cfg.c 2010-07-30 13:58:02 +0000
@@ -47,6 +47,7 @@
#include "value-prof.h"
#include "pointer-set.h"
#include "tree-inline.h"
+#include "target.h"
/* This file contains functions for building the Control Flow Graph (CFG)
for a function tree. */
@@ -7092,6 +7093,9 @@
edge e;
edge_iterator ei;
+ if (!targetm.warn_func_result())
+ return 0;
+
/* If we have a path to EXIT, then we do return. */
if (TREE_THIS_VOLATILE (cfun->decl)
&& EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
|
