Bug 655570 – app-i18n/mozc fails to build with GCC 8

• Product: Gentoo Linux
• Status: RESOLVED FIXED

[Description Meoberto Whagbossa 2018-05-12 09:13:22 UTC]

Created attachment 531028 [details, diff]
Fixes build on GCC8

The problem has already been reported to upstream, but given Google's policy on pull requests, I doubt it will be addressed in a timely manner.

The build logs are as follows:

[597/747] /usr/bin/x86_64-pc-linux-gnu-g++ -MMD -MF obj/engine/engine.engine.o.d -DOS_LINUX -DMOZC_BUILD -DCHANNEL_DEV -DNDEBUG -DQT_NO_DEBUG -DNO_LOGGING -DIGNORE_HELP_FLAG -DIGNORE_INVALID_FLAG -I/var/tmp/portage/app-i18n/mozc-9999/work/mozc-9999/src -Igen -Igen/proto_
out -Wall -Wno-char-subscripts -Wno-sign-compare -Wno-deprecated-declarations -Wwrite-strings -Wno-unknown-warning-option -Wno-inconsistent-missing-override -fPIC -fno-exceptions -fmessage-length=0 -fno-strict-aliasing -funsigned-char -pipe -pthread -fno-omit-frame-point
er -fstack-protector --param=ssp-buffer-size=4 -Wtype-limits -march=native -O2 -pipe -Wno-deprecated -Wno-covered-switch-default -Wno-unnamed-type-template-args -Wno-c++11-narrowing -std=gnu++0x -std=gnu++0x  -c ../../engine/engine.cc -o obj/engine/engine.engine.o
FAILED: obj/engine/engine.engine.o                                                      
/usr/bin/x86_64-pc-linux-gnu-g++ -MMD -MF obj/engine/engine.engine.o.d -DOS_LINUX -DMOZC_BUILD -DCHANNEL_DEV -DNDEBUG -DQT_NO_DEBUG -DNO_LOGGING -DIGNORE_HELP_FLAG -DIGNORE_INVALID_FLAG -I/var/tmp/portage/app-i18n/mozc-9999/work/mozc-9999/src -Igen -Igen/proto_out -Wall
-Wno-char-subscripts -Wno-sign-compare -Wno-deprecated-declarations -Wwrite-strings -Wno-unknown-warning-option -Wno-inconsistent-missing-override -fPIC -fno-exceptions -fmessage-length=0 -fno-strict-aliasing -funsigned-char -pipe -pthread -fno-omit-frame-pointer -fstack
-protector --param=ssp-buffer-size=4 -Wtype-limits -march=native -O2 -pipe -Wno-deprecated -Wno-covered-switch-default -Wno-unnamed-type-template-args -Wno-c++11-narrowing -std=gnu++0x -std=gnu++0x  -c ../../engine/engine.cc -o obj/engine/engine.engine.o
In file included from /usr/lib/gcc/x86_64-pc-linux-gnu/8.1.0/include/g++-v8/bits/stl_algobase.h:66,
                 from /usr/lib/gcc/x86_64-pc-linux-gnu/8.1.0/include/g++-v8/memory:62,
                 from /var/tmp/portage/app-i18n/mozc-9999/work/mozc-9999/src/engine/engine.h:33,
                 from ../../engine/engine.cc:30:
/usr/lib/gcc/x86_64-pc-linux-gnu/8.1.0/include/g++-v8/bits/stl_iterator_base_funcs.h: In instantiation of ‘void std::__advance(_RandomAccessIterator&, _Distance, std::random_access_iterator_tag) [with _RandomAccessIterator = mozc::ZeroQueryDict::iterator; _Distance = lon
g int]’:
/usr/lib/gcc/x86_64-pc-linux-gnu/8.1.0/include/g++-v8/bits/stl_iterator_base_funcs.h:206:21:   required from ‘void std::advance(_InputIterator&, _Distance) [with _InputIterator = mozc::ZeroQueryDict::iterator; _Distance = long int]’
/usr/lib/gcc/x86_64-pc-linux-gnu/8.1.0/include/g++-v8/bits/stl_algo.h:2137:16:   required from ‘std::pair<_FIter, _FIter> std::__equal_range(_ForwardIterator, _ForwardIterator, const _Tp&, _CompareItTp, _CompareTpIt) [with _ForwardIterator = mozc::ZeroQueryDict::iterator
; _Tp = long unsigned int; _CompareItTp = __gnu_cxx::__ops::_Iter_less_val; _CompareTpIt = __gnu_cxx::__ops::_Val_less_iter]’
/usr/lib/gcc/x86_64-pc-linux-gnu/8.1.0/include/g++-v8/bits/stl_algo.h:2190:32:   required from ‘std::pair<_FIter, _FIter> std::equal_range(_FIter, _FIter, const _Tp&) [with _FIter = mozc::ZeroQueryDict::iterator; _Tp = long unsigned int]’
/var/tmp/portage/app-i18n/mozc-9999/work/mozc-9999/src/prediction/zero_query_dict.h:213:57:   required from here
/usr/lib/gcc/x86_64-pc-linux-gnu/8.1.0/include/g++-v8/bits/stl_iterator_base_funcs.h:183:2: error: no match for ‘operator--’ (operand type is ‘mozc::ZeroQueryDict::iterator’)
  --__i;                                       
  ^~~~~


There is a patch for this in the upstream issue report: https://github.com/google/mozc/issues/441

Applyying this patch, the build succeeds using gcc 8.1 and mozc works without any issues whatsoever. With all due credit to farseerfc, the patch is attached to this report.

[Comment 1 Larry the Git Cow 2018-06-13 14:36:44 UTC]

The bug has been closed via the following commit(s):

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=a917a8214bb56d2486898553788d9764a2b26cdc

commit a917a8214bb56d2486898553788d9764a2b26cdc
Author:     Arfrever Frehtes Taifersar Arahesis <[e-mail]>
AuthorDate: 2018-06-01 03:02:06 +0000
Commit:     Mike Gilbert <[e-mail]>
CommitDate: 2018-06-13 14:36:21 +0000

    app-i18n/mozc: Fix building with GCC 8.
    
    Closes: https://bugs.gentoo.org/655570

 app-i18n/mozc/files/mozc-2.23.2815.102-gcc-8.patch | 22 ++++++++++++++++++++++
 app-i18n/mozc/mozc-2.23.2815.102.ebuild            |  1 +
 app-i18n/mozc/mozc-9999.ebuild                     |  1 +
 3 files changed, 24 insertions(+)