Re: bison-generated code causes compilation failure on OpenBSD 4.7

[Jim Meyering]

Jim Meyering wrote:
> Hello,
>
> On an OpenBSD 4.7 system, building coreutils fails like this:
> (noticed in prerelease testing)
>
>   make[2]: Entering directory `/u/guest/meyering/coreutils-8.5.185-0ad44/lib'
>     CC       parse-datetime.o
>     parse-datetime.c:590: error: conflicting types for 'malloc'
>
> The problematic code is from bison's skeleton:
>
> #  ifndef YYMALLOC
> #   define YYMALLOC malloc
> #   if ! defined malloc && ! defined _STDLIB_H && (defined __STDC__ || 
> defined __C99__FUNC__ \
>      || defined __cplusplus || defined _MSC_VER)
> void *malloc (YYSIZE_T); /* INFRINGES ON USER NAME SPACE */
>
> There are two problems.
> First, YYSIZE_T is defined to __SIZE_TYPE__, which is defined
> to "unsigned int" (don't recall where).
> That obviously fails to match the expected "size_t".
>
> Stepping back, malloc shouldn't even be declared here, since
> this skeleton code has already included stdlib.h.
> The code above attempts to detect that by testing for _STDLIB_H,
> but on this system, that symbol is not defined.
> Instead, OpenBSD's stdlib.h spells it as _STDLIB_H_, with
> the added trailing underscore.
>
> When I change the above to this, it solves the problem:
>
> #  ifndef YYMALLOC
> #   define YYMALLOC malloc
> #   if ! defined malloc && ! defined _STDLIB_H && ! defined _STDLIB_H_ \
>      && (defined __STDC__ || defined __C99__FUNC__ \
>      || defined __cplusplus || defined _MSC_VER)
> void *malloc (YYSIZE_T); /* INFRINGES ON USER NAME SPACE */
>
> However, if you like this approach I'm sure you'll want to
> change some of the other uses of _STDLIB_H.
>
> FYI, I regenerated parse-datetime.c with the latest from bison.git's
> master branch, and it's the same.

I found a better way to fix it and am using that
as a temporary work-around, while we wait for a fix in bison:

>From 9e43bb61e60a318da34628989e8a754aee18a285 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Thu, 7 Oct 2010 23:15:00 +0200
Subject: [PATCH] parse-datetime: avoid compilation failure on OpenBSD 4.7

* lib/parse-datetime.y (_STDLIB_H) [_STDLIB_H_]: Define.
This works around a compilation failure on OpenBSD 4.7:
http://thread.gmane.org/gmane.comp.parsers.bison.bugs/3418
---
 ChangeLog            |    7 +++++++
 lib/parse-datetime.y |    8 ++++++++
 2 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 45f2a69..f327621 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2010-10-07  Jim Meyering  <address@hidden>
+
+       parse-datetime: avoid compilation failure on OpenBSD 4.7
+       * lib/parse-datetime.y (_STDLIB_H) [_STDLIB_H_]: Define.
+       This works around a compilation failure on OpenBSD 4.7:
+       http://thread.gmane.org/gmane.comp.parsers.bison.bugs/3418
+
 2010-10-07  Eric Blake  <address@hidden>

        docs: update cygwin progress
diff --git a/lib/parse-datetime.y b/lib/parse-datetime.y
index bc46e1c..a760e69 100644
--- a/lib/parse-datetime.y
+++ b/lib/parse-datetime.y
@@ -68,6 +68,14 @@

 #include "xalloc.h"

+/* Bison's skeleton tests _STDLIB_H, while some stdlib.h headers
+   use _STDLIB_H_ as witness.  Map the latter to the one bison uses.  */
+/* FIXME: this is temporary.  Remove when we have a mechanism to ensure
+   that the version we're using is fixed, too.  */
+#ifdef _STDLIB_H_
+# undef _STDLIB_H
+# define _STDLIB_H 1
+#endif

 /* ISDIGIT differs from isdigit, as follows:
    - Its arg may be any int or unsigned int; it need not be an unsigned char
--
1.7.3.1.104.gc752e