[llvm-dev] Get full cmake lines and prepocessed source for a GCC bug report

[Hans Wennborg via llvm-dev]

On Wed, Aug 29, 2018 at 10:18 AM, Sedat Dilek <sedat.dilek at gmail.com> wrote:
> On Wed, Aug 29, 2018 at 10:14 AM, Hans Wennborg <hans at chromium.org> wrote:
>> On Wed, Aug 29, 2018 at 9:45 AM, Sedat Dilek via llvm-dev
>> <llvm-dev at lists.llvm.org> wrote:
>>> Hi,
>>>
>>> for filing a GCC v8.2.0 bug in Debian/buster AMD64 the Debian/GCC
>>> mainatiners want two things...
>>>
>>> [ FULL CMAKE LINE ]
>>>
>>> How do I configure this in the LLVM/Clang build?
>>> Can I set an option of cmake?
>>>
>>> [ PREPROCESSED SOURCE FILES ]
>>>
>>> How and where do I get the preprocessed source?
>>> Do I need to set options for this in my build-script?
>>
>> From your other email, when the compiler crashed, ninja printed the invocation:
>>
>> /usr/bin/g++-8  -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GNU_SOURCE
>> -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
>> -Ilib/Bitcode/Reader
>> -I/home/sdi/src/llvm-toolchain/llvm/lib/Bitcode/Reader -Iinclude
>> -I/home/sdi/src/llvm-toolchain/llvm/include -fPIC
>> -fvisibility-inlines-hidden -Werror=date-time -std=c++11 -Wall -Wextra
>> -Wno-unused-parameter -Wwrite-strings -Wcast-qual
>> -Wno-missing-field-initializers -pedantic -Wno-long-long
>> -Wno-maybe-uninitialized -Wno-class-memaccess
>> -Wdelete-non-virtual-dtor -Wno-comment -fdiagnostics-color
>> -ffunction-sections -fdata-sections -O3    -UNDEBUG  -fno-exceptions
>> -fno-rtti -MD -MT
>> lib/Bitcode/Reader/CMakeFiles/LLVMBitReader.dir/MetadataLoader.cpp.o
>> -MF lib/Bitcode/Reader/CMakeFiles/LLVMBitReader.dir/MetadataLoader.cpp.o.d
>> -o lib/Bitcode/Reader/CMakeFiles/LLVMBitReader.dir/MetadataLoader.cpp.o
>> -c /home/sdi/src/llvm-toolchain/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
>>
>>
>> To generate preprocessed source from that, you use the -E flag, so
>> adding something like this to the end of command-line should work:
>>
>> -E -o /tmp/preprocessed.ii
>>
>>
>> To see the internal GCC invocation, you can add the -### option to the
>> command. The output of that, and the preprocessed source, should be
>> enough to reproduce the bug.
>>
>
> Thanks, Hans.
>
> I kept the build-directory of my build with my selfmade llvm-toolchain
> v7.0.0rc2.
>
> So I can run this gcc-line directly?

Yes, I think that should work.