Re: [PATCH] mig: silence compiler warnings in generated server code

[Thomas Schwinge]

On Mon, Jul 24, 2006 at 09:55:36AM -0400, Ben Asselstine wrote:
> I couldn't find the offending line in upstream, so I sent it to
> debian-hurd on purpose.  Maybe this is already fixed in upstream?

Seems so, yes.

The following changes (and some more infrastructural changes) are missing
in the Debian package:

#v+
2004-03-18  Roland McGrath  <roland@frob.com>

        * utils.c (do_skip_vfprintf): New macro.
        (WriteCopyType, WritePackMsgType): Use that, so we do va_start and
        va_end independently around each SkipVFPrintf call.

2004-02-10  Roland McGrath  <roland@frob.com>

        * user.c (WriteTypeCheck): Use BAD_TYPECHECK macro instead of type-pun.
        * server.c (WriteTypeCheck): Likewise.
        * utils.c (WriteBogusDefines): Write a #define for that macro.
        * utils.c (WriteCheckDecl): Write auto const, not static const.
        (WriteStaticShortDecl, WriteStaticLongDecl): Likewise.
#v-


> --- mig-1.3.1.orig/server.c   1999-10-11 08:44:49.000000000 +0000
> +++ mig-1.3.1/server.c        2006-07-23 20:06:32.000000000 +0000
> @@ -418,7 +418,7 @@ WriteTypeCheck(FILE *file, register cons
>  
>      fprintf(file, "#if\tTypeCheck\n");
>      if (akCheck(arg->argKind, akbRequestQC))
> -     fprintf(file, "\tif (* (int *) &In%dP->%s != * (int *) &%sCheck)\n",
> +     fprintf(file, "\tif (memcmp (&In%dP->%s, &%sCheck, sizeof (int)))\n",
>               arg->argRequestPos, arg->argTTName, arg->argVarName);
>      else
>      {

That's what Roland did:

utils.c
#v+
@@ -71,6 +71,12 @@
     fprintf(file, "#define\tUseExternRCSId\t\t1\n");
     fprintf(file, "#endif\n");
     fprintf(file, "\n");
+
+    fprintf(file, "#define BAD_TYPECHECK(type, check) ({\\\n");
+    fprintf(file,
+           "  union { mach_msg_type_t t; unsigned32_t w; } _t, _c;\\\n");
+    fprintf(file,
+           "  _t.t = *(type); _c.t = *(check); _t.w != _c.w; })\n");
 }

 void
#v-

server.c
#v+
@@ -418,7 +418,7 @@

     fprintf(file, "#if\tTypeCheck\n");
     if (akCheck(arg->argKind, akbRequestQC))
-       fprintf(file, "\tif (* (int *) &In%dP->%s != * (int *) &%sCheck)\n",
+       fprintf(file, "\tif (BAD_TYPECHECK(&In%dP->%s, &%sCheck))\n",
                arg->argRequestPos, arg->argTTName, arg->argVarName);
     else
     {
#v-


Ben, perhaps you should now nudge the one who is maintaining the Debian
mig package.


Regards,
 Thomas