1 files changed, 11 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/bitfld-21.c b/gcc/testsuite/gcc.dg/bitfld-21.c
new file mode 100644
index 000000000..66f9330f1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/bitfld-21.c
@@ -0,0 +1,11 @@
+/* Test for bit-field widths not integer constant expressions but
+   folding to integer constants: PR 42439.  */
+/* { dg-do compile } */
+/* { dg-options "-O2 -pedantic-errors" } */
+
+void
+f (void)
+{
+  const int m = 1;
+  ((void)(sizeof(struct { int i:!!m; }))); /* { dg-error "not an integer constant expression" } */
+}