[Bug c/25301] New: [3.4 regression] ICE for sizofe of incomplete type

["reichelt at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

The testcase gcc.dg/noncompile/920923-1.c causes an ICE on the 3.4 branch.
A reduced testcase is:

=======================
typedef struct A B;
int i = sizeof(B);
=======================

bug.c:2: error: invalid application of `sizeof' to incomplete type `
Internal compiler error: Error reporting routines re-entered.
Please submit a full bug report, [etc.]

The culprit is the code in c-objc-common.c (c_tree_printer) <case 'T'>:

    case 'T':
      if (TREE_CODE (t) == TYPE_DECL)
        {
          if (DECL_NAME (t))
            n = (*lang_hooks.decl_printable_name) (t, 2);
        }
      else
        {
          t = TYPE_NAME (t);
          if (t)
            n = IDENTIFIER_POINTER (t);
        }
      break;

In the above case t is a RECORD_TYPE, but TYPE_NAME (t) is a TYPE_DECL.
So there's some logic missing to handle this case.


The other problem is that the testcase in the testsuite PASSed
despite the ICE. The comment on top of the testcase says:

  /* This test case contains a large number of syntactic errors.  We
     believe the intent of the test is that the compiler simply not
     crash.  The set of error messages reported is different when the C
     parser is generated with bison 1.50 than 1.35.  It is not worth
     attempting to prevent this.  Instead, we use a single dg-error with
     a regexp that will match _all_ the errors indiscriminately.  The
     old error/warning/etc markers are kept around for reference, but
     disabled.

     Revisit after new (recursive descent) parser is implemented for C.
     -- zw 2002-10-17  */

  /* { dg-error ".*" "many syntax errors" { target *-*-* } 0 } */

Well, the regexp also matches the ICE-message, so the testcase is
now broken. While this is probably hard to fix in 3.4 and 4.0,
the testcase be revisited on mainline and the 4.1 branch where the
new C parser is in place.

I'll file a new PR for this.


-- 
           Summary: [3.4 regression] ICE for sizofe of incomplete type
           Product: gcc
           Version: 3.4.5
            Status: UNCONFIRMED
          Keywords: ice-on-invalid-code, monitored
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: reichelt at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25301