Re: Issues compiling selftests XADD - "Invalid usage of the XADD return value"

[Jesper Dangaard Brouer <brouer@redhat.com>]

On Mon, 18 Jan 2021 16:24:10 +0100
Brendan Jackman <jackmanb@google.com> wrote:

> On Mon, 18 Jan 2021 at 15:38, Jesper Dangaard Brouer <brouer@redhat.com> wrote:
> > I'm compiling from LLVM 'main' branch (commit e6d758de82b6) but it
> > unfortunately fails to compile (see error below).
> >
> > Any recommended LLVM commit id that works?  
> 
> :(
> 
> I'm on 6f4ee6f87060 and things are working.

I got compiling to work on this commit.  But the error below, were
likely caused by my compile machine simply ran out of memory (it "only"
have 16GB RAM).

I reduced the number of parallel jobs (ninja -j6) and have now
successfully compiled devel branch of LLVM.

Now the compile of BPF-selftests is possible again.


> >
> > [...]
> > ../include/llvm/ExecutionEngine/Orc/Shared/RPCUtils.h:1513:27: note: remove ‘std::move’ call
> > ../include/llvm/ExecutionEngine/Orc/Shared/RPCUtils.h:1519:27: warning: moving a local object in a return statement prevents copy elision [-Wpessimizing-move]
> >  1519 |       return std::move(Err);
> >       |                           ^
> > ../include/llvm/ExecutionEngine/Orc/Shared/RPCUtils.h:1519:27: note: remove ‘std::move’ call
> > ../include/llvm/ExecutionEngine/Orc/Shared/RPCUtils.h:1526:29: warning: moving a local object in a return statement prevents copy elision [-Wpessimizing-move]
> >  1526 |         return std::move(Err);
> >       |                             ^
> > ../include/llvm/ExecutionEngine/Orc/Shared/RPCUtils.h:1526:29: note: remove ‘std::move’ call
> > [2237/3183] Building CXX object tools/clang/lib/ASTMatchers/Dynamic/CMakeFiles/obj.clangDynamicASTMatchers.dir/Registry.cpp.o
> > FAILED: tools/clang/lib/ASTMatchers/Dynamic/CMakeFiles/obj.clangDynamicASTMatchers.dir/Registry.cpp.o
> > /usr/lib64/ccache/c++  -DGTEST_HAS_RTTI=0 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools/clang/lib/ASTMatchers/Dynamic -I/home/jbrouer/git/llvm-project/clang/lib/ASTMatchers/Dynamic -I/home/jbrouer/git/llvm-project/clang/include -Itools/clang/include -Iinclude -I/home/jbrouer/git/llvm-project/llvm/include -fPIC -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -fdiagnostics-color -ffunction-sections -fdata-sections -fno-common -Woverloaded-virtual -fno-strict-aliasing -O2 -DNDEBUG    -fno-exceptions -fno-rtti -std=c++14 -MD -MT tools/clang/lib/ASTMatchers/Dynamic/CMakeFiles/obj.clangDynamicASTMatchers.dir/Registry.cpp.o -MF tools/clang/lib/ASTMatchers/Dynamic/CMakeFiles/obj.clangDynamicASTMatchers.dir/Registry.cpp.o.d -o tools/clang/lib/ASTMatchers/Dynamic/CMakeFiles/obj.clangDynamicASTMatchers.dir/Registry.cpp.o -c /home/jbrouer/git/llvm-project/clang/lib/ASTMatchers/Dynamic/Registry.cpp
> > c++: fatal error: Killed signal terminated program cc1plus
> > compilation terminated.
> >
> > [2255/3183] Building CXX object tools/clang/lib/ASTMatchers/CMakeFiles/obj.clangASTMatchers.dir/ASTMatchFinder.cpp.o
> >
> > [2262/3183] Building CXX object tools/clang/lib/Sema/CMakeFiles/obj.clangSema.dir/SemaExpr.cpp.o
> > ninja: build stopped: subcommand failed.  
> 



-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer