On Mon, Jul 11, 2016 at 11:33 AM, Khem Raj <[email protected]> wrote: > On Mon, Jul 11, 2016 at 4:29 AM, Patrick Ohly <[email protected]> wrote: >> Dan McGregor <danismostlikely <at> gmail.com> writes: >>> From: Daniel McGregor <daniel.mcgregor <at> vecima.com> >>> >>> GCC 6 sets the default C++ standard to C++14 and introduces dead store >>> elimination by default. OpenJDK 8 is not ready for either of these >>> changes, so set the C++ standard back to gnu++98 and disable dead >>> store elimination. >>> >>> Switched to using --with-extra-cflags, cxxflags, and ldflags. The added >>> patch fixes building when using those flags, and are needed to get >>> CFLAGS into the JDK build in the native case. >> >> Has anyone tested this on a host system where gcc is still 4.x, like 4.9.2 >> on Debian Wheezy? >> >> I'm finding that -fno-lifetime-dse is also getting passed to the gcc used >> for compiling native binaries (obviously in openjdk-8-native, but also for >> some helper executables in openjdk-8). This then breaks the compilation >> because older gcc rejects that flag. >> >> I've briefly toyed with the patch below which worked for openjdk-8-native, >> but not for openjdk-8. I'm just going to work around it by staying on gcc >> 5.x and clearing these extra flags. >> >> I'm not familiar enough with the openjdk-8 build process to propose a better >> solution, but perhaps someone else has an idea? >> >> diff --git a/meta-java/recipes-core/openjdk/openjdk-8-common.inc >> b/meta-java/recipes-core/openjdk/openjdk-8-common.inc >> index dd3d397..060d828 100644 >> --- a/meta-java/recipes-core/openjdk/openjdk-8-common.inc >> +++ b/meta-java/recipes-core/openjdk/openjdk-8-common.inc >> @@ -237,6 +237,25 @@ EXTRA_OECONF_append = "\ >> --with-update-version=${OPENJDK_UPDATE_VERSION} \ >> " >> >> -CFLAGS_append = " -fno-lifetime-dse -fno-delete-null-pointer-checks" >> -CXXFLAGS_append = " -fno-lifetime-dse -fno-delete-null-pointer-checks" >> +# GCC 6 sets the default C++ standard to C++14 and introduces dead store >> +# elimination by default. OpenJDK 8 is not ready for either of these >> +# changes. >> +FLAGS_GCC6 = "-fno-lifetime-dse -fno-delete-null-pointer-checks" >> + >> +# All supported cross compilers support the compiler flags that were >> +# added to make compilation with gcc6 work. But the host compiler for >> +# native compilation is a different story: it may be too old (for example, >> +# gcc 4.9.2 on Debian Wheezy). In that case we need to check what the >> +# version is and unset the flags when gcc is not yet GCC 6. >> +python () { >> + if d.getVar('PN', True).endswith('-native'): >> + import re, subprocess >> + version = subprocess.check_output(d.expand('${CC} >> --version').split()).decode('utf-8') >> + m = re.search(r'^gcc.* (\d+)(\.\d+)*$', version, re.MULTILINE) >> + if m and int(m.group(1)) < 6: >> + d.setVar('FLAGS_GCC6', '') >> +} >> + >> +CFLAGS_append = " ${FLAGS_GCC6}" >> +CXXFLAGS_append = " ${FLAGS_GCC6}" >> CXX_append = " -std=gnu++98" > > I can see this needed in several other cases too. May be this should be made > a common utility
I agree but this can be done after we fix meta-java case, so we can avoid a bottleneck here. -- Otavio Salvador O.S. Systems http://www.ossystems.com.br http://code.ossystems.com.br Mobile: +55 (53) 9981-7854 Mobile: +1 (347) 903-9750 -- _______________________________________________ Openembedded-devel mailing list [email protected] http://lists.openembedded.org/mailman/listinfo/openembedded-devel
