1 files changed, 102 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/redecl-1.c b/gcc/testsuite/gcc.dg/redecl-1.c
new file mode 100644
index 000000000..6a7d8faec
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/redecl-1.c
@@ -0,0 +1,102 @@
+/* Test for various situations where a new declaration of an
+   identifier conflicts with an earlier declaration which isn't in the
+   same scope.  These are all undefined behavior per C89 sections
+   6.1.2.2p7, 6.1.2.6p2, and 6.3.2.2p2/footnote 38 (C99 6.2.2p7 and
+   6.2.7p2 - implicit declarations are invalid in C99).  */
+
+/* { dg-do compile } */
+/* { dg-options "-std=c89 -pedantic -Wall -Wno-unused" } */
+
+/* Extern at function scope, clashing with extern at file scope */
+
+extern int foo1;		/* { dg-message "note: previous" } */
+extern int bar1(int);		/* { dg-message "note: previous" } */
+
+void test1(void)
+{
+  extern double foo1;		/* { dg-error "conflict" } */
+  extern double bar1(double);	/* { dg-error "conflict" } */
+}
+
+/* Extern at file scope, clashing with extern at function scope */
+
+void test2(void)
+{
+  extern double foo2;		/* { dg-message "note: previous" } */
+  extern double bar2(double);	/* { dg-message "note: previous" } */
+}
+
+extern int foo2;		/* { dg-error "conflict" } */
+extern int bar2(int);		/* { dg-error "conflict" } */
+
+/* Extern at function scope, clashing with extern at earlier function
+   scope.  Also, don't be fooled by a typedef at file scope.  */
+
+typedef float baz3;		/* { dg-bogus } */
+
+void prime3(void)
+{
+  extern int foo3;		/* { dg-message "note: previous" } */
+  extern int bar3(int);		/* { dg-message "note: previous" } */
+  extern int baz3;		/* { dg-message "note: previous" } */
+}
+
+void test3(void)
+{
+  extern double foo3;		/* { dg-error "conflict" } */
+  extern double bar3(double);	/* { dg-error "conflict" } */
+  extern double baz3;		/* { dg-error "conflict" } */
+}
+
+/* Extern at function scope, clashing with previous implicit decl.  */
+
+void prime4(void)
+{
+  bar4();			/* { dg-warning "implicit declaration of function" } */
+}
+
+void test4(void)
+{
+  extern double bar4(double);	/* { dg-error "conflict" } */
+/* { dg-message "note: previous implicit declaration" "" { target *-*-* } 55 } */
+}
+
+/* Implicit decl, clashing with extern at previous function scope.  */
+
+void prime5(void)
+{
+  extern double bar5(double);	/* { dg-message "note: previous declaration" "" } */
+} /* { dg-message "note: previous implicit declaration" "" { target *-*-* } 68 } */
+
+void test5(void)
+{
+  bar5(1);			/* { dg-warning "implicit declaration of function" } */
+} /* { dg-error "incompatible implicit declaration" "" { target *-*-* } 73 } */
+
+/* Extern then static, both at file scope.  */
+
+extern int test6(int);		/* { dg-message "note: previous" "" } */
+static int test6(int x)		/* { dg-error "follows non-static" } */
+{ return x; }
+
+
+/* Extern then static, extern at previous function scope.  */
+
+void prime7(void)
+{
+  extern int test7(int);	/* { dg-message "note: previous" "" } */
+}
+
+static int test7(int x)		/* { dg-error "follows non-static" } */
+{ return x; }
+
+/* Implicit decl then static.  */
+
+void prime8(void)
+{
+  test8();			/* { dg-message "note: previous" "" } */
+                                /* { dg-warning "implicit" "implicit" { target *-*-* } 97 } */
+}
+
+static int test8(int x)		/* { dg-error "follows non-static" } */
+{ return x; }