C++ PATCH for c++/88222, ICE with bit-field with invalid type

[Marek Polacek]

Paolo's recent commit changed

-         pedwarn (input_location, OPT_Wpedantic,
+         pedwarn (declarator->id_loc, OPT_Wpedantic,

but as this testcase shows, declarator might not always be present.  So
let's brace ourselves for that.

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

2018-11-28  Marek Polacek  <pola...@redhat.com>

        PR c++/88222 - ICE with bit-field with invalid type.
        * decl.c (grokdeclarator): Fall back to input_location if declarator
        is null.

        * g++.dg/ext/flexary31.C: New test.

diff --git gcc/cp/decl.c gcc/cp/decl.c
index 1aaf51750ab..8049a71c6f3 100644
--- gcc/cp/decl.c
+++ gcc/cp/decl.c
@@ -12222,7 +12222,8 @@ grokdeclarator (const cp_declarator *declarator,
                  /* Do not warn on flexible array members in system
                     headers because glibc uses them.  */;
                else if (name)
-                 pedwarn (declarator->id_loc, OPT_Wpedantic,
+                 pedwarn ((declarator ? declarator->id_loc : input_location),
+                          OPT_Wpedantic,
                           "ISO C++ forbids flexible array member %qs", name);
                else
                  pedwarn (input_location, OPT_Wpedantic,
diff --git gcc/testsuite/g++.dg/ext/flexary31.C 
gcc/testsuite/g++.dg/ext/flexary31.C
new file mode 100644
index 00000000000..90f8431a2a4
--- /dev/null
+++ gcc/testsuite/g++.dg/ext/flexary31.C
@@ -0,0 +1,8 @@
+// PR c++/88222
+// { dg-options -Wno-pedantic }
+
+typedef char a[];
+
+class S {
+  a : 4; // { dg-error "bit-field" }
+};