From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:37839) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ghEmo-0005Ao-0Q for qemu-devel@nongnu.org; Wed, 09 Jan 2019 09:24:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ghEmm-0006j1-QT for qemu-devel@nongnu.org; Wed, 09 Jan 2019 09:24:49 -0500 Received: from mx1.redhat.com ([209.132.183.28]:46422) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ghEmk-0006eC-6h for qemu-devel@nongnu.org; Wed, 09 Jan 2019 09:24:48 -0500 From: Thomas Huth Date: Wed, 9 Jan 2019 15:24:29 +0100 Message-Id: <1547043869-10520-1-git-send-email-thuth@redhat.com> Subject: [Qemu-devel] [PATCH v2] configure: Force the C standard to gnu99 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Richard Henderson , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , pbonzini@redhat.com, peter.maydell@linaro.org, Markus Armbruster Different versions of GCC and Clang use different versions of the C standard. This repeatedly caused problems already, e.g. with duplicated typedefs: https://lists.gnu.org/archive/html/qemu-devel/2018-11/msg05829.html or with for-loop variable initializers: https://lists.gnu.org/archive/html/qemu-devel/2019-01/msg00237.html To avoid these problems, we should enforce the C language version to the same level for all compilers. Since our minimum compiler versions is GCC v4.8, our best option is "gnu99" right now ("gnu17" is not available there yet, and "gnu11" is marked as "experimental"). Signed-off-by: Thomas Huth --- v2: Use gnu99 instead of gnu11 configure | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/configure b/configure index b9f34af..721ade7 100755 --- a/configure +++ b/configure @@ -105,7 +105,8 @@ update_cxxflags() { for arg in $QEMU_CFLAGS; do case $arg in -Wstrict-prototypes|-Wmissing-prototypes|-Wnested-externs|\ - -Wold-style-declaration|-Wold-style-definition|-Wredundant-decls) + -Wold-style-declaration|-Wold-style-definition|-Wredundant-decls|\ + -std=gnu99) ;; *) QEMU_CXXFLAGS=${QEMU_CXXFLAGS:+$QEMU_CXXFLAGS }$arg @@ -585,7 +586,7 @@ ARFLAGS="${ARFLAGS-rv}" # left shift of signed integers is well defined and has the expected # 2s-complement style results. (Both clang and gcc agree that it # provides these semantics.) -QEMU_CFLAGS="-fno-strict-aliasing -fno-common -fwrapv $QEMU_CFLAGS" +QEMU_CFLAGS="-fno-strict-aliasing -fno-common -fwrapv -std=gnu99 $QEMU_CFLAGS" QEMU_CFLAGS="-Wall -Wundef -Wwrite-strings -Wmissing-prototypes $QEMU_CFLAGS" QEMU_CFLAGS="-Wstrict-prototypes -Wredundant-decls $QEMU_CFLAGS" QEMU_CFLAGS="-D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE $QEMU_CFLAGS" -- 1.8.3.1