python: force detection of posix semaphores support; required by a neutral pancake.

srcpkgs/python/template

@@ -1,10 +1,11 @@
 # Template build file for 'python'.
 pkgname=python
 version=2.7.3
+revision=2
 wrksrc="Python-$version"
 distfiles="http://www.python.org/ftp/python/$version/Python-$version.tar.xz"
-makedepends="libffi-devel zlib-devel readline-devel gdbm-devel openssl-devel expat-devel db-devel ncurses-devel sqlite-devel"
-revision=1
+makedepends="libffi-devel zlib-devel readline-devel gdbm-devel openssl-devel
+expat-devel db-devel ncurses-devel sqlite-devel"
 short_desc="Interpreted, interactive, object-oriented programming language"
 maintainer="Juan RP <xtraeme@gmail.com>"
 homepage="http://www.python.org"
@@ -25,16 +26,17 @@ long_desc="
 pycompile_dirs="usr/lib/python2.7"
 subpackages="$pkgname-devel"
 
-
 do_configure() {
 	# Enable built-in SQLite3 module to load extensions (Arch fix FS#22122)
 	sed -i "/SQLITE_OMIT_LOAD_EXTENSION/d" setup.py
 
+	# Force posix semaphores by default, sem_open requires /dev/shm and
+	# it's not mounted in chroot.
 	export OPT="${XBPS_CFLAGS}"
 	./configure ${CONFIGURE_SHARED_ARGS} --with-threads \
 		--enable-ipv6 --with-signal-module --enable-shared \
 		--with-system-ffi --enable-unicode=ucs4 --with-system-expat \
-		--with-wctype-functions
+		--with-wctype-functions ac_cv_posix_semaphores_enabled=yes
 }
 
 do_build() {