Ensure that configure-script testing for compiler attributes actually works.

The configure script tests for compiler attributes didn't actually enable
enough warnings or provide a proper test harness to determine whether the 
compiler supports the attribute in question or not; this caused gcc 4.1 to
report that it supports 'weakref', but it doesn't actually support it in the
way that is needed for our optional API mechanism. The new configure script
test will properly distinguish between full support and partial support
for this attribute, among others.



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@200764 65c4cc65-6c06-0410-ace0-fbb531ad65f3

2 files changed, 34 insertions, 34 deletions

diff --git a/autoconf/ast_gcc_attribute.m4 b/autoconf/ast_gcc_attribute.m4
index c4488454d..806b39019 100644
--- a/autoconf/ast_gcc_attribute.m4
+++ b/autoconf/ast_gcc_attribute.m4
@@ -5,12 +5,12 @@ AC_DEFUN([AST_GCC_ATTRIBUTE],
 [
 AC_MSG_CHECKING(for compiler 'attribute $1' support)
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x$2" = "x"
 then
 AC_COMPILE_IFELSE(
-	AC_LANG_PROGRAM([void __attribute__(($1)) *test(void *muffin, ...) {}],
+	AC_LANG_PROGRAM([static void __attribute__(($1)) *test(void *muffin, ...) {return (void *) 0;}],
 			[]),
 	AC_MSG_RESULT(yes)
 	AC_DEFINE_UNQUOTED([HAVE_ATTRIBUTE_$1], 1, [Define to 1 if your GCC C compiler supports the '$1' attribute.]),
@@ -18,7 +18,7 @@ AC_COMPILE_IFELSE(
 )
 else
 AC_COMPILE_IFELSE(
-	AC_LANG_PROGRAM([void __attribute__(($2)) *test(void *muffin, ...) {}],
+	AC_LANG_PROGRAM([static void __attribute__(($2)) *test(void *muffin, ...) {return (void *) 0;}],
 			[]),
 	AC_MSG_RESULT(yes)
 	AC_DEFINE_UNQUOTED([HAVE_ATTRIBUTE_$1], 1, [Define to 1 if your GCC C compiler supports the '$1' attribute.]),
diff --git a/configure b/configure
index 926cf7f5a..97015d342 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.ac Revision: 197738 .
+# From configure.ac Revision: 200519 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.63 for asterisk 1.6.
 #
@@ -18015,7 +18015,7 @@ rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute pure' support" >&5
 $as_echo_n "checking for compiler 'attribute pure' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -18025,7 +18025,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((pure)) *test(void *muffin, ...) {}
+static void __attribute__((pure)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18076,7 +18076,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18129,7 +18129,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute malloc' support" >&5
 $as_echo_n "checking for compiler 'attribute malloc' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -18139,7 +18139,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((malloc)) *test(void *muffin, ...) {}
+static void __attribute__((malloc)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18190,7 +18190,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18243,7 +18243,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute const' support" >&5
 $as_echo_n "checking for compiler 'attribute const' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -18253,7 +18253,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((const)) *test(void *muffin, ...) {}
+static void __attribute__((const)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18304,7 +18304,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18357,7 +18357,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute unused' support" >&5
 $as_echo_n "checking for compiler 'attribute unused' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -18367,7 +18367,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((unused)) *test(void *muffin, ...) {}
+static void __attribute__((unused)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18418,7 +18418,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18471,7 +18471,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute always_inline' support" >&5
 $as_echo_n "checking for compiler 'attribute always_inline' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -18481,7 +18481,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((always_inline)) *test(void *muffin, ...) {}
+static void __attribute__((always_inline)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18532,7 +18532,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18585,7 +18585,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute deprecated' support" >&5
 $as_echo_n "checking for compiler 'attribute deprecated' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -18595,7 +18595,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((deprecated)) *test(void *muffin, ...) {}
+static void __attribute__((deprecated)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18646,7 +18646,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18699,7 +18699,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute sentinel' support" >&5
 $as_echo_n "checking for compiler 'attribute sentinel' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -18709,7 +18709,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((sentinel)) *test(void *muffin, ...) {}
+static void __attribute__((sentinel)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18760,7 +18760,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18813,7 +18813,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute warn_unused_result' support" >&5
 $as_echo_n "checking for compiler 'attribute warn_unused_result' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -18823,7 +18823,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((warn_unused_result)) *test(void *muffin, ...) {}
+static void __attribute__((warn_unused_result)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18874,7 +18874,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18927,7 +18927,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute weakref' support" >&5
 $as_echo_n "checking for compiler 'attribute weakref' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "xweakref("foo")" = "x"
 then
@@ -18937,7 +18937,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((weakref)) *test(void *muffin, ...) {}
+static void __attribute__((weakref)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -18988,7 +18988,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((weakref("foo"))) *test(void *muffin, ...) {}
+static void __attribute__((weakref("foo"))) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -19041,7 +19041,7 @@ CFLAGS="$saved_CFLAGS"
 { $as_echo "$as_me:$LINENO: checking for compiler 'attribute weak_import' support" >&5
 $as_echo_n "checking for compiler 'attribute weak_import' support... " >&6; }
 saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Werror"
+CFLAGS="$CFLAGS -Wall -Wno-unused -Werror"
 
 if test "x" = "x"
 then
@@ -19051,7 +19051,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__((weak_import)) *test(void *muffin, ...) {}
+static void __attribute__((weak_import)) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {
@@ -19102,7 +19102,7 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-void __attribute__(()) *test(void *muffin, ...) {}
+static void __attribute__(()) *test(void *muffin, ...) {return (void *) 0;}
 int
 main ()
 {