Disable CPU optimizations not supported by all x86_64 systems.

--- a/cmake/modules/SIMDExt.cmake	2017-03-23 22:22:58.254071694 +0100
+++ b/cmake/modules/SIMDExt.cmake	2017-03-23 22:23:22.446848845 +0100
@@ -5,11 +5,6 @@
 # HAVE_ARM_NEON
 # HAVE_INTEL_SSE
 # HAVE_INTEL_SSE2
-# HAVE_INTEL_SSE3
-# HAVE_INTEL_SSSE3
-# HAVE_INTEL_PCLMUL
-# HAVE_INTEL_SSE4_1
-# HAVE_INTEL_SSE4_2
 #
 # SIMD_COMPILE_FLAGS
 #
@@ -85,26 +80,6 @@
       if(HAVE_INTEL_SSE2)
         set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -msse2")
       endif()
-      CHECK_C_COMPILER_FLAG(-msse3 HAVE_INTEL_SSE3)
-      if(HAVE_INTEL_SSE3)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -msse3")
-      endif()
-      CHECK_C_COMPILER_FLAG(-mssse3 HAVE_INTEL_SSSE3)
-      if(HAVE_INTEL_SSSE3)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -mssse3")
-      endif()
-      CHECK_C_COMPILER_FLAG(-mpclmul HAVE_INTEL_PCLMUL)
-      if(HAVE_INTEL_PCLMUL)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -mpclmul")
-      endif()
-      CHECK_C_COMPILER_FLAG(-msse4.1 HAVE_INTEL_SSE4_1)
-      if(HAVE_INTEL_SSE4_1)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -msse4.1")
-      endif()
-      CHECK_C_COMPILER_FLAG(-msse4.2 HAVE_INTEL_SSE4_2)
-      if(HAVE_INTEL_SSE4_2)
-        set(SIMD_COMPILE_FLAGS "${SIMD_COMPILE_FLAGS} -msse4.2")
-      endif()
     endif(CMAKE_SYSTEM_PROCESSOR MATCHES "amd64|x86_64|AMD64")
   endif(CMAKE_SYSTEM_PROCESSOR MATCHES "i686|amd64|x86_64|AMD64")
 elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "(powerpc|ppc)64le")
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<div class='path'>path: <a href='/guix/log/?id=71005247cd7e77145fb17b3d4b22a803a3078454'>root</a>/<a href='/guix/log/gnu?id=71005247cd7e77145fb17b3d4b22a803a3078454'>gnu</a>/<a href='/guix/log/gnu/services?id=71005247cd7e77145fb17b3d4b22a803a3078454'>services</a>/<a href='/guix/log/gnu/services/rsync.scm?id=71005247cd7e77145fb17b3d4b22a803a3078454'>rsync.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/services/rsync.scm?id=71005247cd7e77145fb17b3d4b22a803a3078454&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-03-04 15:22:58 +0100'>2019-03-04</span></td><td><a href='/guix/commit/gnu/services/rsync.scm?id=56a93cb975ddc33d50183fb122e2aafda026f18e'>services: Use 'file-append' for user account shells.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/cuirass.scm (cuirass-account): Use 'file-append' instead
of #~(string-append #$shadow "/sbin/nologin").
* gnu/services/monitoring.scm (zabbix-server-account): Likewise.
(zabbix-agent-account): Likewise.
* gnu/services/rsync.scm (rsync-account): Likewise.
* gnu/services/ssh.scm (%openssh-accounts): Likewise.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-09-23 21:07:27 +0100'>2017-09-23</span></td><td><a href='/guix/commit/gnu/services/rsync.scm?id=9db7e9be59820190a97de22ba72e71fa25f9d168'>gnu: Add rsync service.</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/guix.texi (Networking Services): Add rsync service documentation.
* gnu/services/rsync.scm (&lt;rsync-configuration&gt;): New file.
* gnu/tests/rsync.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add new files.

Signed-off-by: Christopher Baines &lt;mail@cbaines.net&gt;
</span></span></td><td>Oleg Pykhalov</td></tr>