From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33206) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WGf9P-0001zK-8c for qemu-devel@nongnu.org; Thu, 20 Feb 2014 20:43:44 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WGf9J-0004DB-Tr for qemu-devel@nongnu.org; Thu, 20 Feb 2014 20:43:39 -0500 Received: from mail-pa0-f48.google.com ([209.85.220.48]:33091) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WGf9J-0004D0-Nk for qemu-devel@nongnu.org; Thu, 20 Feb 2014 20:43:33 -0500 Received: by mail-pa0-f48.google.com with SMTP id kx10so2734952pab.21 for ; Thu, 20 Feb 2014 17:43:32 -0800 (PST) Message-ID: <5306AF3B.1060701@ozlabs.ru> Date: Fri, 21 Feb 2014 12:43:23 +1100 From: Alexey Kardashevskiy MIME-Version: 1.0 References: <1392909016-14028-1-git-send-email-peter.maydell@linaro.org> <20140220165819.047aba8c@oc7435384737.ibm.com> In-Reply-To: <20140220165819.047aba8c@oc7435384737.ibm.com> Content-Type: text/plain; charset=KOI8-R Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] configure: check that C++ compiler actually works List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thomas Huth , Peter Maydell Cc: qemu-devel@nongnu.org, patches@linaro.org On 02/21/2014 02:58 AM, Thomas Huth wrote: > On Thu, 20 Feb 2014 15:10:16 +0000 > Peter Maydell wrote: > >> Check that the C++ compiler works with the C compiler; if it >> does not, then don't pass CXX to the build process. This >> fixes a regression where QEMU was no longer building if the >> build environment didn't have a C++ compiler (introduced >> in commit 3144f78b, which incorrectly assumed that rules.mak >> would only see a non-empty $(CXX) if configure had actually >> found a working C++ compiler). >> >> Signed-off-by: Peter Maydell >> Reported-by: Alexey Kardashevskiy >> Reported-by: Thomas Huth >> --- >> Apologies for the breakage for people who were building in >> setups with no C++ compiler -- I should have tested the >> original change more thoroughly. >> >> configure | 29 +++++++++++++++++++++++++++++ >> 1 file changed, 29 insertions(+) >> >> diff --git a/configure b/configure >> index 4648117..6829cbb 100755 >> --- a/configure >> +++ b/configure >> @@ -1289,6 +1289,35 @@ else >> error_exit "\"$cc\" either does not exist or does not work" >> fi >> >> +# Check that the C++ compiler exists and works with the C compiler >> +if has $cxx; then >> + cat > $TMPC <> +int c_function(void); >> +int main(void) { return c_function(); } >> +EOF >> + >> + compile_object >> + >> + cat > $TMPC <> +extern "C" { >> + int c_function(void); >> +} >> +int c_function(void) { return 42; } >> +EOF >> + >> + if (cc=$cxx do_cc $QEMU_CFLAGS -o $TMPE $TMPC $TMPO $LDFLAGS); then >> + # C++ compiler $cxx works ok with C compiler $cc >> + : >> + else >> + echo "C++ compiler $cxx does not work with C compiler $cc" >> + echo "Disabling C++ specific optional code" >> + cxx= >> + fi >> +else >> + echo "No C++ compiler available; disabling C++ specific optional code" >> + cxx= >> +fi >> + >> # Consult white-list to determine whether to enable werror >> # by default. Only enable by default for git builds >> z_version=`cut -f3 -d. $source_path/VERSION` > > Works fine for me now on my system w/o C++ compiler: > Tested-by: Thomas Huth Works for me too, in cross environment for ppc64 on x86_64, Tested-by: Alexey Kardashevskiy Thanks. -- Alexey