[Buildroot] [PATCH] package/qt5/qt5webengine: don't link with libstdc++.a on the host

[Peter Seiderer <ps.report@gmx.net>]

Hello Romain,

On Tue, 26 May 2020 23:02:14 +0200, Romain Naour <romain.naour@gmail.com> wrote:

> Hi Peter,
> 
> Le 24/05/2020 ? 17:58, Romain Naour a ?crit?:
> > While cross-compiling, qt5webengine is building a host tool but
> > want to link the libstdc++ statically. This requires to install
> > libstdc++-static package on the host (Fedora package name).
> > 
> > Otherwise the link fail with:
> > 
> >   [185/185] LINK gn
> >   FAILED: gn
> >   /usr/bin/g++ -O3 -fdata-sections -ffunction-sections -Wl,--gc-sections -Wl,-strip-all -Wl,--as-needed -static-libstdc++ -pthread -o gn -Wl,--start-group tools/gn/gn_main.o base.a gn_lib.a -Wl,--end-group -ldl
> >   /usr/bin/ld?: unable to find -lstdc++
> >   [...]
> >   Project ERROR: GN build error!
> > 
> > Add --no-static-libstdc++ argument to gn.pro to link to
> > libstdc++.so.6 instead of libstdc++.a.
> > 
> > --no-static-libstdc++ has been added by [1] but it force
> > linking statically by default.
> > 
> > [1] https://github.com/qt/qtwebengine-chromium/commit/cfab9198a9917f42cf08b1caf84ab9b71aac1911#diff-905c8f054808213577c0a92d1b704615  
> 
> Did you noticed this issue while building for qt5declarative issue?
> On my pc, the static glibc wasn't installed.

I think the problem is qt5webengine specific as it is the only package compiling
a host build tool GN....

Never observed the problem with qt5webengine, maybe because on OpenSUSE there is
a static libstdc++ provided with the 'normal' libstdc++ devel package, eg.
	$ rpm -qf /usr/lib64/gcc/x86_64-suse-linux/9/libstdc++.a
	libstdc++6-devel-gcc9-9.3.1+git1296-1.7.x86_64

Regards,
Peter

> 
> What do you think?
> 
> Best regards,
> Romain
> 
> > Signed-off-by: Romain Naour <romain.naour@gmail.com>
> > Cc: Ga?l Portay <gael.portay@collabora.com>
> > ---
> >  ...ro-don-t-link-statically-with-libstc.patch | 51 +++++++++++++++++++
> >  1 file changed, 51 insertions(+)
> >  create mode 100644 package/qt5/qt5webengine/0001-gn.pro-don-t-link-statically-with-libstc.patch
> > 
> > diff --git a/package/qt5/qt5webengine/0001-gn.pro-don-t-link-statically-with-libstc.patch b/package/qt5/qt5webengine/0001-gn.pro-don-t-link-statically-with-libstc.patch
> > new file mode 100644
> > index 0000000000..dff3e6c849
> > --- /dev/null
> > +++ b/package/qt5/qt5webengine/0001-gn.pro-don-t-link-statically-with-libstc.patch
> > @@ -0,0 +1,51 @@
> > +From 7ae73da23ad998bd1e63ad213cf7a02e61191951 Mon Sep 17 00:00:00 2001
> > +From: Romain Naour <romain.naour@gmail.com>
> > +Date: Sat, 23 May 2020 19:01:19 +0200
> > +Subject: [PATCH] gn.pro: don't link statically with libstc++
> > +MIME-Version: 1.0
> > +Content-Type: text/plain; charset=UTF-8
> > +Content-Transfer-Encoding: 8bit
> > +
> > +While cross-compiling, qt5webengine is building a host tool but
> > +want to link the libstdc++ statically. This requires to install
> > +libstdc++-static package on the host (Fedora package name).
> > +
> > +Otherwise the link fail with:
> > +
> > +  [185/185] LINK gn
> > +  FAILED: gn
> > +  /usr/bin/g++ -O3 -fdata-sections -ffunction-sections -Wl,--gc-sections -Wl,-strip-all -Wl,--as-needed -static-libstdc++ -pthread -o gn -Wl,--start-group tools/gn/gn_main.o base.a gn_lib.a -Wl,--end-group -ldl
> > +  /usr/bin/ld?: unable to find -lstdc++
> > +  [...]
> > +  Project ERROR: GN build error!
> > +
> > +Add --no-static-libstdc++ argument to gn.pro to link to
> > +libstdc++.so.6 instead of libstdc++.a.
> > +
> > +--no-static-libstdc++ has been added by [1] but it force
> > +linking statically by default.
> > +
> > +[1] https://github.com/qt/qtwebengine-chromium/commit/cfab9198a9917f42cf08b1caf84ab9b71aac1911#diff-905c8f054808213577c0a92d1b704615
> > +
> > +Signed-off-by: Romain Naour <romain.naour@gmail.com>
> > +---
> > + src/buildtools/gn.pro | 3 ++-
> > + 1 file changed, 2 insertions(+), 1 deletion(-)
> > +
> > +diff --git a/src/buildtools/gn.pro b/src/buildtools/gn.pro
> > +index 033202e6..5dd8e241 100644
> > +--- a/src/buildtools/gn.pro
> > ++++ b/src/buildtools/gn.pro
> > +@@ -20,7 +20,8 @@ build_pass|!debug_and_release {
> > + 
> > +             gn_gen_args = --no-last-commit-position --out-path $$out_path \
> > +                           --cc \"$$which($$QMAKE_CC)\" --cxx \"$$which($$QMAKE_CXX)\" \
> > +-                          --ld \"$$which($$QMAKE_LINK)\"
> > ++                          --ld \"$$which($$QMAKE_LINK)\" \
> > ++                          --no-static-libstdc++
> > + 
> > +             msvc:!clang_cl: gn_gen_args += --use-lto
> > + 
> > +-- 
> > +2.25.4
> > +
> >   
>