* c-decl.c (implicitly_declare): Diagnose incompatible implicit

	declarations.

testsuite:
	* gcc.dg/redecl-5.c: New test.
	* gcc.dg/format/attr-6.c: Expect warning for implicit declaration
	of scanf.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@85509 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 19 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/redecl-5.c b/gcc/testsuite/gcc.dg/redecl-5.c
new file mode 100644
index 00000000000..a689295bb85
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/redecl-5.c
@@ -0,0 +1,19 @@
+/* Test for multiple declarations and composite types.  Diagnosis of
+   incompatible implicit declaration.  */
+/* Origin: Joseph Myers <jsm@polyomino.org.uk> */
+/* { dg-do compile } */
+/* { dg-options "-std=c89" } */
+
+void
+f (void)
+{
+  long z(); /* { dg-error "previous implicit declaration" } */
+}
+
+void
+g (void)
+{
+  z(); /* { dg-error "incompatible" } */
+  labs(1); /* { dg-warning "incompatible" } */
+  printf("x"); /* { dg-warning "incompatible" } */
+}