[PATCH]: Fix GLX crashes on RISC cpus.

[David Miller]

From: Jaymz Julian <jaymz at artificial-stupidity.net>
Date: Thu, 27 Dec 2007 22:35:34 +1100

> It's not random (it rotates the result in a specific way), but that's not the
> point - you can easily check for this bevaviour by doing something like:
> 
> (warning: written into email client :-p.  Bonus points if you modify
> it to check endian at the same time)

Actually we can't implement this as a run-time check, I just tried.

The problem is that we can't handle cross-compilation cases properly.

Having a default for things that enable or disable features because of
a lack of a run-time check during cross-compilation is one thing, but
having to make a choice which might result in emitting incorrect code
is not OK.

One could argue that we could add the cpu-type check in the
cross-compilation case, but if we need the hard-coded cpu list for
correctness in all cases anyways, there is no point to the run-time
check at all.

Therefore, I think the original patch is the way to go, explicitly
adding cases per cpu type to xserver/configure.ac

Could someone please therefore check my patch in?  Here it is again
for reference.  Thanks!

[GL]: Add GLX compile flags lost in modular X server changes.

RISC chips that trap on unaligned loads and stores need to
define __GLX_ALIGN64.  This used to get added to the cflags
in the old *.cf files but it no longer does in the modular
X server.

Also, Alpha needs to pass -mieee to the compiler as well.

This is a simple backport of a patch that debian, and probably other
distributions, have been applying forever.  To the best of my
knowledge the patch was written by Jurij Smakov.  See debian bug
number #388125.

I just checked and this has been rotting for more than a year in
freedesktop bugzilla as #8392.

Signed-off-by: David S. Miller <davem at davemloft.net>
---
 GL/glx/Makefile.am          |    3 ++-
 configure.ac                |   10 ++++++++++
 hw/dmx/glxProxy/Makefile.am |    1 +
 3 files changed, 13 insertions(+), 1 deletions(-)

diff --git a/GL/glx/Makefile.am b/GL/glx/Makefile.am
index 8eda153..4cf56e8 100644
--- a/GL/glx/Makefile.am
+++ b/GL/glx/Makefile.am
@@ -14,7 +14,8 @@ AM_CFLAGS = \
 	-I at MESA_SOURCE@/src/mesa/glapi \
 	-I at MESA_SOURCE@/src/mesa/main \
 	-DXFree86Server \
-	@GLX_DEFINES@
+	@GLX_DEFINES@ \
+	@GLX_ARCH_DEFINES@
 
 # none yet
 #sdk_HEADERS =
diff --git a/configure.ac b/configure.ac
index 0b718c9..0742040 100644
--- a/configure.ac
+++ b/configure.ac
@@ -304,6 +304,7 @@ case $host_cpu in
 	        *freebsd*)	SYS_LIBS=-lio ;;
 		*netbsd*)	AC_DEFINE(USE_ALPHA_PIO, 1, [NetBSD PIO alpha IO]) ;;
 	esac
+	GLX_ARCH_DEFINES="-D__GLX_ALIGN64 -mieee"
 	;;
   arm*)
 	ARM_VIDEO=yes
@@ -333,6 +334,7 @@ case $host_cpu in
 	xorg_loader_sparcmuldiv="yes"
 	SPARC64_VIDEO=yes
 	BSD_ARCH_SOURCES="sparc64_video.c ioperm_noop.c"
+	GLX_ARCH_DEFINES="-D__GLX_ALIGN64"
 	;;
   x86_64*|amd64*)
   	use_x86_asm="yes"
@@ -347,8 +349,16 @@ case $host_cpu in
 				SYS_LIBS=-lamd64
 				;;
 	esac
+	GLX_ARCH_DEFINES="-D__GLX_ALIGN64"
+	;;
+  ia64*)
+  	GLX_ARCH_DEFINES="-D__GLX_ALIGN64"
+	;;
+  s390*)
+  	GLX_ARCH_DEFINES="-D__GLX_ALIGN64"
 	;;
 esac
+AC_SUBST(GLX_ARCH_DEFINES)
 
 dnl BSD *_video.c selection
 AM_CONDITIONAL(ALPHA_VIDEO, [test "x$ALPHA_VIDEO" = xyes])
diff --git a/hw/dmx/glxProxy/Makefile.am b/hw/dmx/glxProxy/Makefile.am
index 1fbc8d7..f995498 100644
--- a/hw/dmx/glxProxy/Makefile.am
+++ b/hw/dmx/glxProxy/Makefile.am
@@ -32,6 +32,7 @@ libglxproxy_a_SOURCES = compsize.c \
                         unpack.h
 
 AM_CFLAGS = \
+            @GLX_ARCH_DEFINES@ \
             $(DIX_CFLAGS) \
             -I$(top_srcdir)/hw/dmx \
             -I$(top_srcdir)/include \