8233880: Support compilers with multi-digit major version numbers

Reviewed-by: tbell

make/autoconf/toolchain.m4

@@ -461,7 +461,7 @@ AC_DEFUN([TOOLCHAIN_EXTRACT_COMPILER_VERSION],
     COMPILER_VERSION_STRING=`$ECHO $COMPILER_VERSION_OUTPUT | \
         $SED -e 's/ *Copyright .*//'`
     COMPILER_VERSION_NUMBER=`$ECHO $COMPILER_VERSION_OUTPUT | \
-        $SED -e 's/^.* \(@<:@1-9@:>@\.@<:@0-9.@:>@*\)@<:@^0-9.@:>@.*$/\1/'`
+        $SED -e 's/^.* \(@<:@1-9@:>@<:@0-9@:>@*\.@<:@0-9.@:>@*\)@<:@^0-9.@:>@.*$/\1/'`
   elif test  "x$TOOLCHAIN_TYPE" = xclang; then
     # clang --version output typically looks like
     #    Apple LLVM version 5.0 (clang-500.2.79) (based on LLVM 3.3svn)