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[PATCH] libc: Don't use a custom wrapper macro around __has_include.
- From: Emilio Cobos Álvarez <emilio at crisal dot io>
- To: libc-alpha at sourceware dot org
- Cc: Emilio Cobos Álvarez <emilio at crisal dot io>
- Date: Tue, 12 Nov 2019 19:31:15 +0100
- Subject: [PATCH] libc: Don't use a custom wrapper macro around __has_include.
This causes issues when using clang with -frewrite-includes to e.g., submit the
translation unit to a distributed compiler.
In my case, I was building Firefox using sccache.
See https://bugs.llvm.org/show_bug.cgi?id=43982 for a reduced test-case since I
initially thought this was a clang bug.
Apparently doing this is invalid C++ per:
* http://eel.is/c++draft/cpp.cond#7.sentence-2
(See https://bugs.llvm.org/show_bug.cgi?id=37990)
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
---
misc/sys/cdefs.h | 8 --------
sysdeps/unix/sysv/linux/bits/statx.h | 14 ++++++++------
2 files changed, 8 insertions(+), 14 deletions(-)
diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
index abcb0d5e3c..467dbd9547 100644
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -412,14 +412,6 @@
# define __glibc_has_attribute(attr) 0
#endif
-#ifdef __has_include
-/* Do not use a function-like macro, so that __has_include can inhibit
- macro expansion. */
-# define __glibc_has_include __has_include
-#else
-# define __glibc_has_include(header) 0
-#endif
-
#if (!defined _Noreturn \
&& (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
&& !__GNUC_PREREQ (4,7))
diff --git a/sysdeps/unix/sysv/linux/bits/statx.h b/sysdeps/unix/sysv/linux/bits/statx.h
index ff3f2e8973..14d5992226 100644
--- a/sysdeps/unix/sysv/linux/bits/statx.h
+++ b/sysdeps/unix/sysv/linux/bits/statx.h
@@ -26,12 +26,14 @@
/* Use "" to work around incorrect macro expansion of the
__has_include argument (GCC PR 80005). */
-#if __glibc_has_include ("linux/stat.h")
-# include "linux/stat.h"
-# ifdef STATX_TYPE
-# define __statx_timestamp_defined 1
-# define __statx_defined 1
-# endif
+#ifdef __has_include
+# if __has_include("linux/stat.h")
+# include "linux/stat.h"
+# ifdef STATX_TYPE
+# define __statx_timestamp_defined 1
+# define __statx_defined 1
+# endif
+# endif
#endif
#include <bits/statx-generic.h>
--
2.24.0