[Mesa-dev] [PATCH 1/2] Add target attribute check to configure

[Marc Dietrich]

The target attribute allows for function or file specific compiler target
specification. This will be useful when compiling with LTO enabled.

Signed-off-by: Marc Dietrich <marvin24 at gmx.de>
---
 configure.ac                | 2 ++
 m4/ax_gcc_func_attribute.m4 | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/configure.ac b/configure.ac
index c72fe92..233a04c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -153,8 +153,10 @@ AX_GCC_FUNC_ATTRIBUTE([flatten])
 AX_GCC_FUNC_ATTRIBUTE([format])
 AX_GCC_FUNC_ATTRIBUTE([malloc])
 AX_GCC_FUNC_ATTRIBUTE([packed])
+AX_GCC_FUNC_ATTRIBUTE([target])
 
 AM_CONDITIONAL([GEN_ASM_OFFSETS], test "x$GEN_ASM_OFFSETS" = xyes)
+AM_CONDITIONAL([HAVE_TARGET_ATTRIBUTE], test "x${ax_cv_have_func_attribute_target}" = xyes)
 
 dnl Make sure the pkg-config macros are defined
 m4_ifndef([PKG_PROG_PKG_CONFIG],
diff --git a/m4/ax_gcc_func_attribute.m4 b/m4/ax_gcc_func_attribute.m4
index 4e0ecbb..00c8794 100644
--- a/m4/ax_gcc_func_attribute.m4
+++ b/m4/ax_gcc_func_attribute.m4
@@ -175,6 +175,15 @@ AC_DEFUN([AX_GCC_FUNC_ATTRIBUTE], [
                 [pure], [
                     int foo( void ) __attribute__(($1));
                 ],
+                [target], [
+                    #if defined(__i386__) || defined(__x86_64__)
+                    __attribute__(($1("sse4.1"))) int foo ( void ) { return 0; }
+                    #elif defined(__powerpc__) || defined(__ppc64__)
+                    __attribute__(($1("altivec"))) int foo ( void ) { return 0; }
+                    #else
+                    #error unsupported architecture
+                    #endif
+                ],
                 [unused], [
                     int foo( void ) __attribute__(($1));
                 ],
-- 
2.2.1