[committed] avoid more invalid redeclarations (PR 97955)

[Martin Sebor via Gcc-patches]

The attached trivial patch, committed in r11-5325, avoids failing
with an ICE when attempting to check the arguments of an invalid
function redeclaration.

Martin

PR c/97955 - ICE in build_array_type_1 on invalid redeclaration of function with VLA parameter

gcc/c-family/ChangeLog:

	* c-warn.c (warn_parm_array_mismatch): Avoid invalid redeclarations.

gcc/testsuite/ChangeLog:

	* gcc.dg/pr97955.c: New test.

diff --git a/gcc/c-family/c-warn.c b/gcc/c-family/c-warn.c
index 6d22a113ad0..91abafe49b1 100644
--- a/gcc/c-family/c-warn.c
+++ b/gcc/c-family/c-warn.c
@@ -3379,8 +3379,9 @@ warn_parm_array_mismatch (location_t origloc, tree fndecl, tree newparms)
 	return;
 
       /* Only check pointers and C++ references.  */
+      tree curptype = TREE_TYPE (curp);
       tree newptype = TREE_TYPE (newp);
-      if (!POINTER_TYPE_P (newptype))
+      if (!POINTER_TYPE_P (curptype) || !POINTER_TYPE_P (newptype))
 	continue;
 
       /* Skip mismatches in __builtin_va_list that is commonly
@@ -3430,7 +3431,6 @@ warn_parm_array_mismatch (location_t origloc, tree fndecl, tree newparms)
       if (origloc == UNKNOWN_LOCATION)
 	origloc = newloc;
 
-      tree curptype = TREE_TYPE (curp);
       const std::string newparmstr = newa->array_as_string (newptype);
       const std::string curparmstr = cura->array_as_string (curptype);
       if (new_vla_p && !cur_vla_p)
diff --git a/gcc/testsuite/gcc.dg/pr97955.c b/gcc/testsuite/gcc.dg/pr97955.c
new file mode 100644
index 00000000000..a5236c76c94
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr97955.c
@@ -0,0 +1,7 @@
+/* PR 97955 - ICE in build_array_type_1 on invalid redeclaration of function
+   with VLA parameter
+   { dg-do compile }
+   { dg-options "-Wall" } */
+
+void f (int n, int a[n]);
+void f (int *b) { }           // { dg-error "conflicting types" }