Hi!
Some time ago, by chance, I had found that libgomp's config.h/libgomp.h
produce different results depending in which combination/order they're
being included. As I remember, this caused different results in/with the
following libgomp.h section:
#if !defined (HAVE_ATTRIBUTE_VISIBILITY) \
|| !defined (HAVE_ATTRIBUTE_ALIAS) \
|| !defined (HAVE_AS_SYMVER_DIRECTIVE) \
|| !defined (PIC) \
|| !defined (HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
# undef LIBGOMP_GNU_SYMBOL_VERSIONING
#endif
..., and then caused different results for the following users of
LIBGOMP_GNU_SYMBOL_VERSIONING. Maybe this should be fixed differently
(to make inclusion order of these files idempotent), but will the
following be OK for now (for gcc-6-branch and/or trunk?) to fix the
status quo?
commit 075063cb8611bb479289b6e0c80a54d94fc3a14e
Author: Thomas Schwinge <tho...@codesourcery.com>
Date: Tue Nov 10 16:56:01 2015 +0100
Resolve idempotency issue with libgomp's config.h/libgomp.h
libgomp/
* configure.ac: Instantiate AH_TOP to add an #include guard.
* config.h.in: Regenerate.
* configure: Regenerate.
* libgomp.h: Include "config.h" early.
* oacc-cuda.c: Include "libgomp.h" early, don't include
"config.h".
* oacc-int.h: Likewise.
* oacc-mem.c: Likewise.
* plugin/plugin-nvptx.c: Likewise.
* target.c: Likewise.
---
libgomp/config.h.in | 6 ++++++
libgomp/configure | 5 +++--
libgomp/configure.ac | 5 +++++
libgomp/libgomp.h | 8 ++++++--
libgomp/oacc-cuda.c | 3 +--
libgomp/oacc-int.h | 2 +-
libgomp/oacc-mem.c | 3 +--
libgomp/plugin/plugin-nvptx.c | 2 +-
libgomp/target.c | 1 -
9 files changed, 24 insertions(+), 11 deletions(-)
diff --git libgomp/config.h.in libgomp/config.h.in
index 226ac53..1ef51ca 100644
--- libgomp/config.h.in
+++ libgomp/config.h.in
@@ -1,5 +1,11 @@
/* config.h.in. Generated from configure.ac by autoheader. */
+
+ #ifdef LIBGOMP_H
+ # error Must not #include "config.h" after #include "libgomp.h".
+ #endif
+
+
/* Define to 1 if the target assembler supports .symver directive. */
#undef HAVE_AS_SYMVER_DIRECTIVE
diff --git libgomp/configure libgomp/configure
index 8d03eb6..327bd1b 100755
--- libgomp/configure
+++ libgomp/configure
@@ -2592,6 +2592,7 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
ac_config_headers="$ac_config_headers config.h"
+
# -------
# Options
# -------
@@ -11145,7 +11146,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 11148 "configure"
+#line 11149 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
@@ -11251,7 +11252,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 11254 "configure"
+#line 11255 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
diff --git libgomp/configure.ac libgomp/configure.ac
index 2e41ca8..b9a665f 100644
--- libgomp/configure.ac
+++ libgomp/configure.ac
@@ -4,6 +4,11 @@
AC_PREREQ(2.64)
AC_INIT([GNU Offloading and Multi Processing Runtime Library], 1.0,,[libgomp])
AC_CONFIG_HEADER(config.h)
+AH_TOP([
+ #ifdef LIBGOMP_H
+ # error Must not #include "config.h" after #include "libgomp.h".
+ #endif
+])
# -------
# Options
diff --git libgomp/libgomp.h libgomp/libgomp.h
index 664e76b..6a05bbc 100644
--- libgomp/libgomp.h
+++ libgomp/libgomp.h
@@ -33,7 +33,12 @@
that are part of the external ABI, and the lower case prefix "gomp"
is used group items that are completely private to the library. */
-#ifndef LIBGOMP_H
+#ifndef LIBGOMP_H
+/* We #include "config.h" early, before we #define LIBGOMP_H, so that we can
+ use the latter to check in "config.h" that it's not being included again,
+ which might conflict with configuration changes done further down in
+ libgomp.h. */
+#include "config.h"
#define LIBGOMP_H 1
#ifndef _LIBGOMP_CHECKING_
@@ -41,7 +46,6 @@
#define _LIBGOMP_CHECKING_ 0
#endif
-#include "config.h"
#include "gstdint.h"
#include "libgomp-plugin.h"
diff --git libgomp/oacc-cuda.c libgomp/oacc-cuda.c
index 86a2a77..115697d 100644
--- libgomp/oacc-cuda.c
+++ libgomp/oacc-cuda.c
@@ -26,9 +26,8 @@
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
-#include "openacc.h"
-#include "config.h"
#include "libgomp.h"
+#include "openacc.h"
#include "oacc-int.h"
void *
diff --git libgomp/oacc-int.h libgomp/oacc-int.h
index db0a937..7fd9e95 100644
--- libgomp/oacc-int.h
+++ libgomp/oacc-int.h
@@ -38,8 +38,8 @@
#ifndef OACC_INT_H
#define OACC_INT_H 1
+#include "libgomp.h"
#include "openacc.h"
-#include "config.h"
#include <stddef.h>
#include <stdbool.h>
#include <stdarg.h>
diff --git libgomp/oacc-mem.c libgomp/oacc-mem.c
index ce1905c..0d98a7f 100644
--- libgomp/oacc-mem.c
+++ libgomp/oacc-mem.c
@@ -26,9 +26,8 @@
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
-#include "openacc.h"
-#include "config.h"
#include "libgomp.h"
+#include "openacc.h"
#include "gomp-constants.h"
#include "oacc-int.h"
#include <stdint.h>
diff --git libgomp/plugin/plugin-nvptx.c libgomp/plugin/plugin-nvptx.c
index 4b57833..fc5f298 100644
--- libgomp/plugin/plugin-nvptx.c
+++ libgomp/plugin/plugin-nvptx.c
@@ -31,8 +31,8 @@
is not clear as to what that state might be. Or how one might
propagate it from one thread to another. */
+#include "libgomp.h"
#include "openacc.h"
-#include "config.h"
#include "libgomp-plugin.h"
#include "oacc-plugin.h"
#include "gomp-constants.h"
diff --git libgomp/target.c libgomp/target.c
index e2dd0e0..dd6f74d 100644
--- libgomp/target.c
+++ libgomp/target.c
@@ -25,7 +25,6 @@
/* This file contains the support of offloading. */
-#include "config.h"
#include "libgomp.h"
#include "oacc-plugin.h"
#include "oacc-int.h"
Grüße
Thomas
