Compilation fails in several places due to uncommented switch/case statements which are supposed to fall through. Reproducible: Always Steps to Reproduce: 1.emerge dev-lang/rust Actual Results: --- stderr /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/support/command-line.cpp: In member function 'void wasm::Options::parse(int, const char**)': /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/support/command-line.cpp:112:11: error: this statement may fall through [-Werror=implicit-fallthrough=] if (positionalsSeen) { ^~ /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/support/command-line.cpp:118:9: note: here case Arguments::N: ^~~~ /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/support/command-line.cpp:150:9: error: this statement may fall through [-Werror=implicit-fallthrough=] if (option->seen) { ^~ /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/support/command-line.cpp:156:7: note: here case Arguments::N: ^~~~ cc1plus: all warnings being treated as errors gmake[3]: *** [src/support/CMakeFiles/support.dir/build.make:135: src/support/CMakeFiles/support.dir/command-line.cpp.o] Error 1 gmake[3]: *** Waiting for unfinished jobs.... gmake[2]: *** [CMakeFiles/Makefile2:830: src/support/CMakeFiles/support.dir/all] Error 2 gmake[2]: *** Waiting for unfinished jobs.... /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/emscripten-optimizer/optimizer-shared.cpp: In function 'AsmSign detectSign(cashew::Ref, cashew::IString)': /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/emscripten-optimizer/optimizer-shared.cpp:157:9: error: this statement may fall through [-Werror=implicit-fallthrough=] if (op == TRSHIFT) return ASM_UNSIGNED; ^~ /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/emscripten-optimizer/optimizer-shared.cpp:159:7: note: here case '|': // fallthrough ^~~~ cc1plus: all warnings being treated as errors gmake[3]: *** [src/emscripten-optimizer/CMakeFiles/emscripten-optimizer.dir/build.make:63: src/emscripten-optimizer/CMakeFiles/emscripten-optimizer.dir/optimizer-shared.cpp.o] Error 1 gmake[2]: *** [CMakeFiles/Makefile2:720: src/emscripten-optimizer/CMakeFiles/emscripten-optimizer.dir/all] Error 2 gmake[1]: *** [CMakeFiles/Makefile2:172: CMakeFiles/binaryen.dir/rule] Error 2 gmake: *** [Makefile:190: binaryen] Error 2 I tried to fix one of the affected locations (see attached patch), hoping that it was the only one, but then come the next ones... :-(
Created attachment 521062 [details, diff] patch for one of the failing places
Are you running with unconventional compiler flags here? I'm not sure why you see this and I don't.
What do you mean with "unconventional" compiler flags? Are these here "unconventional": CFLAGS="-O2 -g -ggdb -gdwarf-4 -march=native -mtune=native -mpopcnt -fomit-frame-pointer -frename-registers -pipe" As you see, I do not set any "warning" related options and the -Werror=... does definitely not come from me! Obviously the author has had the same kinds of warnings before, as he already has used "//fallthrough" statements in many many places - but not 100% consequently. So it looks like an upstream problem... I have absolutely no idea why I shall be the one and only human being on this planet who has that problem... Maybe it be that you use a different compiler? I use: sys-devel/gcc-7.2.0-r1:7.2.0 (I can switch to sys-devel/gcc-7.3.0:7.3.0 and try again, but I don't expect any change)
Might be helpful to just post your full emerge --info. By unconventional, I simply mean that you are using flags that all other users so far are not using (since yours is the first bug report about this). I think you might be better off working with upstream, since this does not appear to be a packaging issue.
Well, the CFLAGS that I use do not have any influence. I tried with generic flags: CFLAGS="-O2 -mtune=native" CXXFLAGS="-O2 -mtune=native" emerge -uv1 =dev-lang/rust-1.23.0-r1:stable/1.23::gentoo =virtual/rust-1.23.0::gentoo But that doesn't affect the command line that is failing in any way. If I scroll back a bit, I can see a cmake invocation that checks for some extra flags. There you can clearly see how it probes for "-Werror" !!! running: "cmake" "/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/librustc_binaryen/../binaryen" "-DBUILD_STATIC_LIB=ON" "-DCMAKE_INSTALL_PREFIX=/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/build/rustc_binaryen-d16520c0277199c9/out" "-DCMAKE_C_FLAGS= -ffunction-sections -fdata-sections -fPIC -ffunction-sections -fdata-sections -fPIC -mtune=native -m64 -m64" "-DCMAKE_C_COMPILER=/usr/lib64/ccache/bin/x86_64-pc-linux-gnu-gcc" "-DCMAKE_CXX_FLAGS= -ffunction-sections -fdata-sections -fPIC -ffunction-sections -fdata-sections -fPIC -mtune=native -m64 -m64" "-DCMAKE_CXX_COMPILER=/usr/lib64/ccache/bin/x86_64-pc-linux-gnu-g++" "-DCMAKE_BUILD_TYPE=Release" -- The C compiler identification is GNU 7.2.0 -- The CXX compiler identification is GNU 7.2.0 -- Check for working C compiler: /usr/lib64/ccache/bin/x86_64-pc-linux-gnu-gcc -- Check for working C compiler: /usr/lib64/ccache/bin/x86_64-pc-linux-gnu-gcc -- works -- Detecting C compiler ABI info -- Detecting C compiler ABI info - done -- Detecting C compile features -- Detecting C compile features - done -- Check for working CXX compiler: /usr/lib64/ccache/bin/x86_64-pc-linux-gnu-g++ -- Check for working CXX compiler: /usr/lib64/ccache/bin/x86_64-pc-linux-gnu-g++ -- works -- Detecting CXX compiler ABI info -- Detecting CXX compiler ABI info - done -- Detecting CXX compile features -- Detecting CXX compile features - done -- Looking for pthread.h -- Looking for pthread.h - found -- Looking for pthread_create -- Looking for pthread_create - not found -- Check if compiler accepts -pthread -- Check if compiler accepts -pthread - yes -- Found Threads: TRUE -- Building with -std=c++11 -- Building for platform x86-64 -- Building with -Wall -- Building with -Werror -- Building with -Wextra -- Building with -Wno-unused-parameter -- Building with -fno-omit-frame-pointer -- Building with -fPIC -- Building with -O2 -- Building with -UNDEBUG -- Configuring done -- Generating done -- Build files have been written to: /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/build/rustc_binaryen-d16520c0277199c9/out/build running: "cmake" "--build" "." "--target" "binaryen" "--config" "Release" "--" Scanning dependencies of target ir Scanning dependencies of target wasm [...] [ 82%] Building CXX object src/passes/CMakeFiles/passes.dir/Vacuum.cpp.o [ 83%] Linking CXX static library ../../lib/libpasses.a [ 83%] Built target passes --- stderr /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/emscripten-optimizer/optimizer-shared.cpp: In function 'AsmSign detectSign(cashew::Ref, cashew::IString)': /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/emscripten-optimizer/optimizer-shared.cpp:157:9: error: this statement may fall through [-Werror=implicit-fallthrough=] if (op == TRSHIFT) return ASM_UNSIGNED; ^~ /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/binaryen/src/emscripten-optimizer/optimizer-shared.cpp:159:7: note: here case '|': // fallthrough ^~~~ cc1plus: all warnings being treated as errors gmake[3]: *** [src/emscripten-optimizer/CMakeFiles/emscripten-optimizer.dir/build.make:63: src/emscripten-optimizer/CMakeFiles/emscripten-optimizer.dir/optimizer-shared.cpp.o] Error 1 gmake[3]: *** Waiting for unfinished jobs.... gmake[2]: *** [CMakeFiles/Makefile2:720: src/emscripten-optimizer/CMakeFiles/emscripten-optimizer.dir/all] Error 2 gmake[2]: *** Waiting for unfinished jobs.... gmake[1]: *** [CMakeFiles/Makefile2:172: CMakeFiles/binaryen.dir/rule] Error 2 gmake: *** [Makefile:190: binaryen] Error 2 thread 'main' panicked at ' command did not execute successfully, got: exit code: 2 build script failed, must exit now', src/vendor/cmake/src/lib.rs:631:4 note: Run with `RUST_BACKTRACE=1` for a backtrace. warning: build failed, waiting for other jobs to finish... error: build failed thread 'main' panicked at 'command did not execute successfully: "/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rust-stage0/bin/cargo" "build" "--target" "x86_64-unknown-linux-gnu" "-j" "5" "-v" "--release" "--locked" "--frozen" "--features" " jemalloc llvm" "--manifest-path" "/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/rustc/Cargo.toml" "--message-format" "json" expected success, got: exit code: 101', src/bootstrap/compile.rs:877:8 note: Run with `RUST_BACKTRACE=1` for a backtrace. Traceback (most recent call last): File "./x.py", line 20, in <module> bootstrap.main() File "/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/bootstrap/bootstrap.py", line 758, in main bootstrap() File "/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/bootstrap/bootstrap.py", line 749, in bootstrap run(args, env=env, verbose=build.verbose) File "/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/src/bootstrap/bootstrap.py", line 148, in run raise RuntimeError(err) RuntimeError: failed to run: /var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/build/bootstrap/debug/bootstrap build --verbose --config=/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src/config.toml -j5 * ERROR: dev-lang/rust-1.23.0-r1::gentoo failed (compile phase): * (no error message) * * Call stack: * ebuild.sh, line 124: Called src_compile * environment, line 2223: Called die * The specific snippet of code: * ./x.py build --verbose --config="${S}"/config.toml -j$(makeopts_jobs) || die * * If you need support, post the output of `emerge --info '=dev-lang/rust-1.23.0-r1::gentoo'`, * the complete build log and the output of `emerge -pqv '=dev-lang/rust-1.23.0-r1::gentoo'`. * The complete build log is located at '/var/tmp/portage/dev-lang/rust-1.23.0-r1/temp/build.log'. * The ebuild environment file is located at '/var/tmp/portage/dev-lang/rust-1.23.0-r1/temp/environment'. * Working directory: '/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src' * S: '/var/tmp/portage/dev-lang/rust-1.23.0-r1/work/rustc-1.23.0-src' >>> Failed to emerge dev-lang/rust-1.23.0-r1
Created attachment 521524 [details] output of emerge --info ...
Interesting! Perhaps it's the compiler version? I'm still on gcc-6.4.
update: I made it build now, by passing special CFLAGS (including "-Wno-implicit-fallthrough") : CFLAGS="-O2 -mtune=native -Wno-implicit-fallthrough" CXXFLAGS="-O2 -mtune=native -Wno-implicit-fallthrough" emerge -uv1 =dev-lang/rust-1.23.0-r1:stable/1.23::gentoo =virtual/rust-1.23.0::gentoo
I can confirm this. I was not able to compile rust-1.23-r1 with gcc 7.3. Adding the flags Thomas described made it build and install...
Going to close this as obsolete, please reopen if you still see this with 1.30.1.
