avoid hang in GNU ld/as detection when non-GNU utility reads from stdin (Mac OS X)

gcc/gcc.spec

@@ -37,7 +37,7 @@ Class:        CORE
 Group:        Compiler
 License:      GPL
 Version:      %{V_full}
-Release:      20070605
+Release:      20070608
 
 #   package options
 %option       with_cxx       yes
@@ -119,8 +119,8 @@ AutoReqProv:  no
     AS="%{l_tool_locate as as}"
     echo "$LD" | grep "^/" >/dev/null && l_with_gnu_ld_as="${l_with_gnu_ld_as} --with-ld=\"$LD\""
     echo "$AS" | grep "^/" >/dev/null && l_with_gnu_ld_as="${l_with_gnu_ld_as} --with-as=\"$AS\""
-    "$LD" --version 2>/dev/null | grep "^GNU ld "        >/dev/null && l_with_gnu_ld_as="${l_with_gnu_ld_as} --with-gnu-ld"
-    "$AS" --version 2>/dev/null | grep "^GNU assembler " >/dev/null && l_with_gnu_ld_as="${l_with_gnu_ld_as} --with-gnu-as"
+    "$LD" --version </dev/null 2>/dev/null | grep "^GNU ld "        >/dev/null && l_with_gnu_ld_as="${l_with_gnu_ld_as} --with-gnu-ld"
+    "$AS" --version </dev/null 2>/dev/null | grep "^GNU assembler " >/dev/null && l_with_gnu_ld_as="${l_with_gnu_ld_as} --with-gnu-as"
 
     #   determine threads usage
 %if "%{with_threads}" == "yes"