From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:38542) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ggSPX-0006rg-2M for qemu-devel@nongnu.org; Mon, 07 Jan 2019 05:45:36 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ggSPW-0004Y7-5a for qemu-devel@nongnu.org; Mon, 07 Jan 2019 05:45:35 -0500 Received: from mx1.redhat.com ([209.132.183.28]:56556) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ggSPW-0004UW-07 for qemu-devel@nongnu.org; Mon, 07 Jan 2019 05:45:34 -0500 From: Thomas Huth Date: Mon, 7 Jan 2019 11:45:26 +0100 Message-Id: <1546857926-5958-1-git-send-email-thuth@redhat.com> Subject: [Qemu-devel] [PATCH] configure: Force the C standard to gnu11 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 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 are GCC v4.8 and Clang v3.4 now, and both basically support "gnu11" already, this seems to be a good choice. Signed-off-by: Thomas Huth --- configure | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/configure b/configure index 79375af..07f8105 100755 --- a/configure +++ b/configure @@ -107,6 +107,9 @@ update_cxxflags() { -Wstrict-prototypes|-Wmissing-prototypes|-Wnested-externs|\ -Wold-style-declaration|-Wold-style-definition|-Wredundant-decls) ;; + -std=gnu11) + QEMU_CXXFLAGS=${QEMU_CXXFLAGS:+$QEMU_CXXFLAGS }-std=gnu++11 + ;; *) QEMU_CXXFLAGS=${QEMU_CXXFLAGS:+$QEMU_CXXFLAGS }$arg ;; @@ -585,7 +588,7 @@ ARFLAGS="${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=gnu11 $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