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=7316f137dc1679baaf3dcaa180ce15966a2e3bd7'>root</a>/<a href='/guix/log/NEWS?id=7316f137dc1679baaf3dcaa180ce15966a2e3bd7'>NEWS</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/NEWS?id=7316f137dc1679baaf3dcaa180ce15966a2e3bd7&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-05-17 11:25:51 +0200'>2019-05-17</span></td><td><a href='/guix/commit/NEWS?id=c34684b6bc32c76b2383cf3641dad1b059fd84fc'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-05-16 18:52:27 +0200'>2019-05-16</span></td><td><a href='/guix/commit/NEWS?id=22872f766615ed5ae300b6bc1212e3001f46a0e9'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-05-01 12:10:42 +0200'>2019-05-01</span></td><td><a href='/guix/commit/NEWS?id=6298c3ffd9654d3231a6f25390b056483e8f407c'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-04-29 11:31:23 +0200'>2019-04-29</span></td><td><a href='/guix/commit/NEWS?id=2f8198dfed1de935dfc60510a5514e5c289c3fc7'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-04-28 22:57:07 +0200'>2019-04-28</span></td><td><a href='/guix/commit/NEWS?id=7dac61143d9911ad02e239a44b17bd40f06d47a6'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-12-05 00:11:22 +0100'>2018-12-05</span></td><td><a href='/guix/commit/NEWS?id=eeedb094ec93ac63e92f733165a3e6883f6002ba'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-12-05 00:08:28 +0100'>2018-12-05</span></td><td><a href='/guix/commit/NEWS?id=273cce9875a1deba2b6669099e69824db55c9622'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-11-23 15:42:01 +0100'>2018-11-23</span></td><td><a href='/guix/commit/NEWS?id=4bd5b9707e14bd5ad4da6868687ff3c642705ce3'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-08-30 15:22:30 +0200'>2018-08-30</span></td><td><a href='/guix/commit/NEWS?id=0f377aad75314df6c6296f4172801519315d81cd'>Update NEWS.</a></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-07-05 22:16:39 +0200'>2018-07-05</span></td><td><a href='/guix/commit/NEWS?id=359fdda40f754bbf1b5dc261e7427b75463b59be'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-07-05 17:19:09 +0200'>2018-07-05</span></td><td><a href='/guix/commit/NEWS?id=1400776f529317c6c3529a0fda2b728e48a621a2'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-06-20 23:47:08 +0200'>2018-06-20</span></td><td><a href='/guix/commit/NEWS?id=414ee4edc9e6fcadba366072a7ebabf3e3c6f26a'>Update NEWS.</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-05-29 14:05:11 +0200'>2018-05-29</span></td><td><a href='/guix/commit/NEWS?id=55a433ebb0b2deb69141619d0a0b1e298a969c36'>Update NEWS.</a></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-05-20 21:42:32 +0300'>2018-05-20</span></td><td><a href='/guix/commit/NEWS?id=e9d271ed9a1fba86f372986a137b6110a41a1324'>services: Add Enlightenment desktop service.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-05-08 21:55:46 -0700'>2018-05-08</span></td><td><a href='/guix/commit/NEWS?id=ede121de426f9c56820852888a0b370f0ccbce49'>guix: Separate the package name and version with "@", not "-".</a><span class='msg-avail'>...</span></td><td>Chris Marusich</td></tr>