misc/cgo/testsanitizers: do not run with clang < 3.8 and Linux ≥ 4.1

These are simply incompatible. Clang fixed the bug but not in older versions.

Fixes #12898.

Change-Id: I74a3fd9134dadab6d0f074f8fd09e00d64558d7a
Reviewed-on: https://go-review.googlesource.com/17254Reviewed-by: Ian Lance Taylor <iant@golang.org>

misc/cgo/testsanitizers/test.bash

@@ -29,10 +29,24 @@ if $CC --version | grep clang >& /dev/null; then
   ver=$($CC --version | sed -e 's/.* version \([0-9.-]*\).*/\1/')
   major=$(echo $ver | sed -e 's/\([0-9]*\).*/\1/')
   minor=$(echo $ver | sed -e 's/[0-9]*\.\([0-9]*\).*/\1/')
-  if test $major -lt 3 || test $major -eq 3 -a $minor -lt 6; then
-    echo "skipping msan test; clang version $major.$minor older than 3.6"
+  if test "$major" -lt 3 || test "$major" -eq 3 -a "$minor" -lt 6; then
+    echo "skipping msan test; clang version $major.$minor (older than 3.6)"
     exit 0
   fi
+  
+  # Clang before 3.8 does not work with Linux at or after 4.1.
+  # golang.org/issue/12898.
+  if test "$major" -lt 3 || test "$major" -eq 3 -a "$minor" -lt 8; then
+    if test "$(uname)" = Linux; then
+      linuxver=$(uname -r)
+      linuxmajor=$(echo $ver | sed -e 's/\([0-9]*\).*/\1/')
+      linuxminor=$(echo $ver | sed -e 's/[0-9]*\.\([0-9]*\).*/\1/')
+      if test "$linuxmajor" -gt 4 || test "$linuxmajor" -eq 4 -a "$linuxminor" -ge 1; then
+        echo "skipping msan test; clang version $major.$minor (older than 3.8) incompatible with linux version $linuxmajor.$linuxminor (4.1 or newer)"
+        exit 0
+      fi
+    fi
+  fi
 fi
 
 status=0