On a new Haiku/x86_64, testing a POSIX testdir produces a build failure:
In file included from ../../gltests/test-limits-h.c:23:
../../gltests/../gllib/verify.h:216:41: error: static assertion failed: "verify
((0x7fffffffffffffffL) >> ((32) - 1 - (((-0x7fffffffffffffffL - 1L)) < 0)) ==
1)"
# define _GL_VERIFY(R, DIAGNOSTIC, ...) _Static_assert (R, DIAGNOSTIC)
^~~~~~~~~~~~~~
../../gltests/../gllib/verify.h:276:20: note: in expansion of macro '_GL_VERIFY'
# define verify(R) _GL_VERIFY (R, "verify (" #R ")", -)
^~~~~~~~~~
../../gltests/test-limits-h.c:30:3: note: in expansion of macro 'verify'
verify ((max) >> ((width) - 1 - ((min) < 0)) == 1)
^~~~~~
../../gltests/test-limits-h.c:51:1: note: in expansion of macro 'verify_width'
verify_width (LONG_BIT, LONG_MIN, LONG_MAX);
^~~~~~~~~~~~
The reason is that LONG_BIT was defined to 32 instead of 64. This happens in
this gnulib code:
# if LONG_MAX == INT_MAX
# define LONG_BIT 32
# else
# define LONG_BIT 64
# endif
Here, LONG_MAX and INT_MAX were both not defined yet, so evaluated to 0
in the preprocessor directive. This is because the system's <limits.h>
does #include_next <limits.h> and thus ends up including gnulib's limits.h
recursively.
This patch fixes it.
2020-05-08 Bruno Haible <br...@clisp.org>
limits-h: Define LONG_BIT correctly on Haiku/x86_64.
* lib/limits.in.h: Define and test _GL_ALREADY_INCLUDING_LIMITS_H.
diff --git a/lib/limits.in.h b/lib/limits.in.h
index d8d1916..9103d2d 100644
--- a/lib/limits.in.h
+++ b/lib/limits.in.h
@@ -15,16 +15,32 @@
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, see <https://www.gnu.org/licenses/>. */
-#ifndef _@GUARD_PREFIX@_LIMITS_H
-
#if __GNUC__ >= 3
@PRAGMA_SYSTEM_HEADER@
#endif
@PRAGMA_COLUMNS@
-/* The include_next requires a split double-inclusion guard. */
+#if defined _GL_ALREADY_INCLUDING_LIMITS_H
+/* Special invocation convention:
+ On Haiku/x86_64, we have a sequence of nested includes
+ <limits.h> -> <syslimits.h> -> <limits.h>.
+ In this situation, LONG_MAX and INT_MAX are not yet defined,
+ therefore we should not attempt to define LONG_BIT. */
+
#@INCLUDE_NEXT@ @NEXT_LIMITS_H@
+#else
+/* Normal invocation convention. */
+
+#ifndef _@GUARD_PREFIX@_LIMITS_H
+
+# define _GL_ALREADY_INCLUDING_LIMITS_H
+
+/* The include_next requires a split double-inclusion guard. */
+# @INCLUDE_NEXT@ @NEXT_LIMITS_H@
+
+# undef _GL_ALREADY_INCLUDING_LIMITS_H
+
#ifndef _@GUARD_PREFIX@_LIMITS_H
#define _@GUARD_PREFIX@_LIMITS_H
@@ -102,3 +118,4 @@
#endif /* _@GUARD_PREFIX@_LIMITS_H */
#endif /* _@GUARD_PREFIX@_LIMITS_H */
+#endif
