In a testdir on Android, I see many compilation errors here:
clang++ -ferror-limit=0 -DHAVE_CONFIG_H -DEXEEXT=\"\" -DEXEEXT=\"\" -I.
-I../../gltests -I.. -DGNULIB_STRICT_CHECKING=1 -DIN_GNULIB_TESTS=1 -I.
-I../../gltests -I.. -I../../gltests/.. -I../gllib -I../../gltests/../gllib
-I/data/data/com.termux/files/home/local/include -Wall -Wno-error -g -O2 -c -o
test-math-c++2.o ../../gltests/test-math-c++2.cc
In file included from ../../gltests/test-math-c++2.cc:20:
In file included from /data/data/com.termux/files/usr/include/c++/v1/cmath:304:
In file included from /data/data/com.termux/files/usr/include/c++/v1/math.h:301:
In file included from ../gllib/stdlib.h:36:
In file included from
/data/data/com.termux/files/usr/include/c++/v1/stdlib.h:20:
In file included from /data/data/com.termux/files/usr/include/stdlib.h:34:
In file included from ../gllib/malloc.h:42:
In file included from /data/data/com.termux/files/usr/include/malloc.h:30:
In file included from ../gllib/stdio.h:71:
In file included from ../gllib/sys/stat.h:44:
In file included from ../gllib/time.h:47:
In file included from /data/data/com.termux/files/usr/include/time.h:33:
In file included from ../gllib/sys/time.h:39:
In file included from /data/data/com.termux/files/usr/include/sys/time.h:37:
In file included from ../gllib/sys/select.h:102:
In file included from /data/data/com.termux/files/usr/include/sys/select.h:40:
In file included from ../gllib/signal.h:75:
In file included from ../gllib/pthread.h:56:
In file included from ../gllib/stdlib.h:28:
In file included from
/data/data/com.termux/files/usr/include/c++/v1/stdlib.h:100:
../gllib/math.h:773:19: error: no member named 'acosf' in the global namespace
_GL_CXXALIAS_SYS (acosf, float, (float x));
~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
...
The problem is that
- /usr/include/c++/v1/math.h indirectly includes gllib/math.h before
/usr/include/math.h has been included,
- The line '#include_next <math.h>' in gllib/math.h includes
/usr/include/c++/v1/math.h, which expands to empty since it is being
included.
This patch fixes it.
2023-01-10 Bruno Haible <br...@clisp.org>
math: Fix compilation errors in C++ mode on Android.
* lib/math.in.h: Declare nothing if this file gets included from
/usr/include/c++/v1/math.h too early.
diff --git a/lib/math.in.h b/lib/math.in.h
index f3d58afc0d..a1cb22936b 100644
--- a/lib/math.in.h
+++ b/lib/math.in.h
@@ -15,6 +15,11 @@
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/>. */
+/* On Android, in C++ mode, when /usr/include/c++/v1/math.h is being included
+ and /usr/include/math.h has not yet been included, skip this file, since it
+ would lead to many syntax errors. */
+#if !(defined __ANDROID__ && defined _LIBCPP_MATH_H && !defined INFINITY)
+
#ifndef _@GUARD_PREFIX@_MATH_H
#if __GNUC__ >= 3
@@ -2725,3 +2730,4 @@ _GL_INLINE_HEADER_END
#endif /* _@GUARD_PREFIX@_MATH_H */
#endif /* _GL_INCLUDING_MATH_H */
#endif /* _@GUARD_PREFIX@_MATH_H */
+#endif
