Bug#55601: BUILD/check-cpu in mysql-trunk is broken on Mac OS X 10.5

Restore the original behavior of check-cpu with respect to core2.
It isn't used as a actual target processor type, but as a mean to
perform other kinds of architecture checks.

BUILD/check-cpu

@@ -7,6 +7,79 @@
 # check_cpu_args : Arguments for GCC compiler settings
 #
 
+check_compiler_cpu_flags () {
+  # different compiler versions have different option names
+  # for CPU specific command line options
+  if test -z "$CC" ; then
+    cc="gcc";
+  else
+    cc=$CC
+  fi
+
+  # check if compiler is gcc and dump its version
+  cc_verno=`$cc -dumpversion 2>/dev/null`
+  if test "x$?" = "x0" ; then
+    set -- `echo $cc_verno | tr '.' ' '`
+    cc_ver="GCC"
+    cc_major=$1
+    cc_minor=$2
+    cc_patch=$3
+    cc_comp=`expr $cc_major '*' 100 '+' $cc_minor`
+  fi
+
+  case "$cc_ver--$cc_verno" in
+    *GCC*)
+        # different gcc backends (and versions) have different CPU flags
+        case `gcc -dumpmachine` in
+          i?86-* | x86_64-*)
+	    if test "$cc_comp" -lt 304 ; then
+              check_cpu_cflags="-mcpu=${cpu_arg}"
+            elif test "$cc_comp" -ge 402 ; then
+              check_cpu_cflags="-mtune=native"
+            else
+              check_cpu_cflags="-mtune=${cpu_arg}"
+            fi
+            ;;
+          ppc-*)
+              check_cpu_cflags="-mcpu=${cpu_arg} -mtune=${cpu_arg}"
+            ;;
+          *)
+            check_cpu_cflags=""
+            return
+            ;;
+        esac
+      ;;
+    2.95.*)
+      # GCC 2.95 doesn't expose its name in --version output
+      check_cpu_cflags="-m${cpu_arg}"
+      ;;
+    *)
+      check_cpu_cflags=""
+      return
+      ;;
+  esac
+
+  # now we check whether the compiler really understands the cpu type
+  touch __test.c
+
+  while [ "$cpu_arg" ] ; do
+    printf "testing $cpu_arg ... " >&2
+
+    # compile check
+    eval "$cc -c $check_cpu_cflags __test.c" 2>/dev/null
+    if test "x$?" = "x0" ; then
+      echo ok >&2
+      break;
+    fi
+
+    echo failed >&2
+    check_cpu_cflags=""
+    break;
+  done
+  rm __test.*
+  return 0
+}
+
 check_cpu () {
   CPUINFO=/proc/cpuinfo
   if test -n "$TEST_CPUINFO" ; then
@@ -179,83 +252,14 @@ check_cpu () {
     return
   fi
 
-  # different compiler versions have different option names
-  # for CPU specific command line options
-  if test -z "$CC" ; then
-    cc="gcc";
-  else
-    cc=$CC
+  if test "x$compiler" = "x" ; then
+    check_compiler_cpu_flags
   fi
 
   if test "x$core2" = "xyes" ; then
     cpu_arg="core2"
   fi
 
-  if test "x$compiler" != "x" ; then
-    return 0
-  fi
-
-  # check if compiler is gcc and dump its version
-  cc_verno=`$cc -dumpversion 2>/dev/null`
-  if test "x$?" = "x0" ; then
-    set -- `echo $cc_verno | tr '.' ' '`
-    cc_ver="GCC"
-    cc_major=$1
-    cc_minor=$2
-    cc_patch=$3
-    cc_comp=`expr $cc_major '*' 100 '+' $cc_minor`
-  fi
-
-  case "$cc_ver--$cc_verno" in
-    *GCC*)
-        # different gcc backends (and versions) have different CPU flags
-        case `gcc -dumpmachine` in
-          i?86-* | x86_64-*)
-	    if test "$cc_comp" -lt 304 ; then
-              check_cpu_cflags="-mcpu=${cpu_arg}"
-            elif test "$cc_comp" -ge 402 ; then
-              check_cpu_cflags="-mtune=native"
-            else
-              check_cpu_cflags="-mtune=${cpu_arg}"
-            fi
-            ;;
-          ppc-*)
-              check_cpu_cflags="-mcpu=${cpu_arg} -mtune=${cpu_arg}"
-            ;;
-          *)
-            check_cpu_cflags=""
-            return
-            ;;
-        esac
-      ;;
-    2.95.*)
-      # GCC 2.95 doesn't expose its name in --version output
-      check_cpu_cflags="-m${cpu_arg}"
-      ;;
-    *)
-      check_cpu_cflags=""
-      return
-      ;;
-  esac
-
-  # now we check whether the compiler really understands the cpu type
-  touch __test.c
-
-  while [ "$cpu_arg" ] ; do
-    printf "testing $cpu_arg ... " >&2
-
-    # compile check
-    eval "$cc -c $check_cpu_cflags __test.c" 2>/dev/null
-    if test "x$?" = "x0" ; then
-      echo ok >&2
-      break;
-    fi
-
-    echo failed >&2
-    check_cpu_cflags=""
-    break;
-  done
-  rm __test.*
   return 0
 }