x11-libs/pixman: fix building with Clang

Gentoo-Bug: https://bugs.gentoo.org/566048

Package-Manager: portage-2.2.28

2 files changed, 99 insertions, 1 deletions

diff --git a/x11-libs/pixman/files/pixman-0.32.8-clang.patch b/x11-libs/pixman/files/pixman-0.32.8-clang.patch
new file mode 100644
index 000000000000..d5319292fbd8
--- /dev/null
+++ b/x11-libs/pixman/files/pixman-0.32.8-clang.patch
@@ -0,0 +1,93 @@
+From d24b415f3e2753a588759d028b811e1ce38fea6c Mon Sep 17 00:00:00 2001
+From: Andrea Canciani <ranma42@gmail.com>
+Date: Sun, 11 Oct 2015 09:45:57 +0200
+Subject: mmx: Improve detection of support for "K" constraint
+
+Older versions of clang emitted an error on the "K" constraint, but at
+least since version 3.7 it is supported. Just like gcc, this
+constraint is only allowed for constants, but apparently clang
+requires them to be known before inlining.
+
+Using the macro definition _mm_shuffle_pi16(A, N) ensures that the "K"
+constraint is always applied to a literal constant, independently from
+the compiler optimizations and allows building pixman-mmx on modern
+clang.
+
+Reviewed-by: Matt Turner <mattst88@gmail.com>
+Signed-off-by: Andrea Canciani <ranma42@gmail.com>
+
+diff --git a/configure.ac b/configure.ac
+index 2178126..3a66909 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -347,15 +347,27 @@ AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+ #error "Need GCC >= 3.4 for MMX intrinsics"
+ #endif
+ #include <mmintrin.h>
++#include <stdint.h>
++
++/* Check support for block expressions */
++#define _mm_shuffle_pi16(A, N)						\
++    ({									\
++	__m64 ret;							\
++									\
++	/* Some versions of clang will choke on K */ 			\
++	asm ("pshufw %2, %1, %0\n\t"					\
++	     : "=y" (ret)						\
++	     : "y" (A), "K" ((const int8_t)N)				\
++	);								\
++									\
++	ret;								\
++    })
++
+ int main () {
+     __m64 v = _mm_cvtsi32_si64 (1);
+     __m64 w;
+ 
+-    /* Some versions of clang will choke on K */
+-    asm ("pshufw %2, %1, %0\n\t"
+-        : "=y" (w)
+-        : "y" (v), "K" (5)
+-    );
++    w = _mm_shuffle_pi16(v, 5);
+ 
+     /* Some versions of clang will choke on this */
+     asm ("pmulhuw %1, %0\n\t"
+diff --git a/pixman/pixman-mmx.c b/pixman/pixman-mmx.c
+index 05c48a4..dec3974 100644
+--- a/pixman/pixman-mmx.c
++++ b/pixman/pixman-mmx.c
+@@ -89,21 +89,7 @@ _mm_mulhi_pu16 (__m64 __A, __m64 __B)
+     return __A;
+ }
+ 
+-#  ifdef __OPTIMIZE__
+-extern __inline __m64 __attribute__((__gnu_inline__, __always_inline__, __artificial__))
+-_mm_shuffle_pi16 (__m64 __A, int8_t const __N)
+-{
+-    __m64 ret;
+-
+-    asm ("pshufw %2, %1, %0\n\t"
+-	: "=y" (ret)
+-	: "y" (__A), "K" (__N)
+-    );
+-
+-    return ret;
+-}
+-#  else
+-#   define _mm_shuffle_pi16(A, N)					\
++# define _mm_shuffle_pi16(A, N)						\
+     ({									\
+ 	__m64 ret;							\
+ 									\
+@@ -114,7 +100,6 @@ _mm_shuffle_pi16 (__m64 __A, int8_t const __N)
+ 									\
+ 	ret;								\
+     })
+-#  endif
+ # endif
+ #endif
+ 
+-- 
+cgit v0.10.2
+
diff --git a/x11-libs/pixman/pixman-0.32.8.ebuild b/x11-libs/pixman/pixman-0.32.8.ebuild
index cefd42305df7..e612abc0ca83 100644
--- a/x11-libs/pixman/pixman-0.32.8.ebuild
+++ b/x11-libs/pixman/pixman-0.32.8.ebuild
@@ -1,8 +1,9 @@
-# Copyright 1999-2015 Gentoo Foundation
+# Copyright 1999-2016 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
 # $Id$
 
 EAPI=5
+XORG_EAUTORECONF=yes
 XORG_MULTILIB=yes
 inherit xorg-2 toolchain-funcs versionator
 
@@ -16,6 +17,10 @@ RDEPEND="abi_x86_32? (
 	!app-emulation/emul-linux-x86-gtklibs[-abi_x86_32(-)]
 	)"
 
+PATCHES=(
+	"${FILESDIR}/${P}-clang.patch"
+)
+
 src_configure() {
 	XORG_CONFIGURE_OPTIONS=(
 		$(use_enable cpu_flags_x86_mmxext mmx)