--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/cpp/if-2.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,28 @@
+/* { dg-do preprocess } */
+/* { dg-options -pedantic-errors } */
+
+#if 'a' != 'a' || '\001' != 1 || '\x12' != 0x12
+#error a,1,0x12 /* { dg-bogus "#error" "basic charconst recognition" } */
+#endif
+
+#if 'a' != L'a'
+#error L'a'	/* { dg-bogus "error" "wide charconst recognition 1" } */
+#endif
+
+#if L'\xfeed' != 0xfeed && L'\xfeed' != (0xfeed - 0x10000)
+#error 0xfeed	/* { dg-bogus "error" "wide charconst recognition 2" } */
+#endif
+
+#if L'\x1234' != 0x1234
+#error 0x1234	/* { dg-bogus "error" "wide charconst recognition 3" } */
+#endif
+
+/* The 'character constant (is )?too long' message is produced by 16-bit targets.  */
+#if 'abcd' /* { dg-warning "(multi-character character constant)|(character constant (is )?too long)" "multi-character charconst" } */
+#endif
+
+#if 'abcdefghi' /* { dg-warning "character constant (is )?too long" "charconst too long" } */
+#endif
+
+#if '' /* { dg-error "empty character constant" "empty charconst" } */
+#endif