diff --git a/gcc/testsuite/lib/target-supports.exp b/gcc/testsuite/lib/target-supports.exp
index 0eb40c6714c..bee879efa21 100644
--- a/gcc/testsuite/lib/target-supports.exp
+++ b/gcc/testsuite/lib/target-supports.exp
@@ -1474,6 +1474,23 @@ proc check_effective_target_powerpc_altivec { } {
     }
 }
 
+# Return 1 if this is a PowerPC 405 target.  The check includes options
+# specified by dg-options for this test, so don't cache the result.
+
+proc check_effective_target_powerpc_405_nocache { } {
+    if { [istarget powerpc*-*-*] || [istarget rs6000-*-*] } {
+	return [check_no_compiler_messages_nocache powerpc_405 object {
+	    #ifdef __PPC405__
+	    int dummy;
+	    #else
+	    #error not a PPC405
+	    #endif
+	} [current_compiler_flags]]
+    } else {
+	return 0
+    }
+}
+
 # Return 1 if this is a SPU target with a toolchain that
 # supports automatic overlay generation.