[C PATCH] Fix ICE-on-invalid with old-style-parameter-declaration and enum (PR c/71266)

[Marek Polacek]

ICE-on-invalid on old-style-parameter-declaration arising from adding a bogus
parameter to the vector of parameters (seen_args).  Skipping such parameters 
prevents the ICE later on.

Bootstrapped/regtested on x86_64-linux, ok for trunk?

2016-05-25  Marek Polacek  <pola...@redhat.com>

        PR c/71266
        * c-decl.c (store_parm_decls_oldstyle): Skip non-PARM_DECLs.

        * gcc.dg/noncompile/old-style-parm-3.c: New test.

diff --git gcc/c/c-decl.c gcc/c/c-decl.c
index 9441fbb..96bd491 100644
--- gcc/c/c-decl.c
+++ gcc/c/c-decl.c
@@ -8605,8 +8605,11 @@ store_parm_decls_oldstyle (tree fndecl, const struct 
c_arg_info *arg_info)
            continue;
          /* If we got something other than a PARM_DECL it is an error.  */
          if (TREE_CODE (decl) != PARM_DECL)
-           error_at (DECL_SOURCE_LOCATION (decl),
-                     "%qD declared as a non-parameter", decl);
+           {
+             error_at (DECL_SOURCE_LOCATION (decl),
+                       "%qD declared as a non-parameter", decl);
+             continue;
+           }
          /* If the declaration is already marked, we have a duplicate
             name.  Complain and ignore the duplicate.  */
          else if (seen_args.contains (decl))
diff --git gcc/testsuite/gcc.dg/noncompile/old-style-parm-3.c 
gcc/testsuite/gcc.dg/noncompile/old-style-parm-3.c
index e69de29..f9d6d0f 100644
--- gcc/testsuite/gcc.dg/noncompile/old-style-parm-3.c
+++ gcc/testsuite/gcc.dg/noncompile/old-style-parm-3.c
@@ -0,0 +1,9 @@
+/* PR c/71266 */
+/* { dg-do compile } */
+
+int fn1 (a)
+  enum b {  /* { dg-warning "empty declaration" } */
+    a /* { dg-error ".a. declared as a non-parameter" } */
+  };
+{
+}

        Marek