[llvm-dev] can't build/run after adding lib to Fibonacci example, even reverting the complete llvm tree does not help (original) (raw)

Dennis Luehring via llvm-dev llvm-dev at lists.llvm.org
Fri Sep 21 22:11:56 PDT 2018

first: thank you for helping out

I might try compiling your source from the VS's Developer Command Prompt: cmake --build . --target Fibonacci Does this work?

call "C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Auxiliary\Build\vcvars64.bat" cd llvm-build cmake --build . --config Debug --target Fibonacci

building Fibonacci example works BUT X86CommonTableGen get rebuild again?

Das Projekt "D:\projects\fun\jit_tests\clang_from_src\llvm-build\lib\Target\X86\InstPrinter\LLVMX86AsmPrinter.vcxproj" (37) erstellt "D:\projects\fun\jit_tests\clang_from_src\llvm-build\lib\Target\X86\X86CommonTableGen.vcxproj" (38) auf Knoten "1" (Standardziele). InitializeBuildStatus: "x64\Debug\X86CommonTableGen\X86Commo.1917F16D.tlog\unsuccessfulbuild" wird erstellt, da "AlwaysCreate" angegeben wurde. CustomBuild:   Building X86GenAsmMatcher.inc...   Building X86GenAsmWriter.inc...   Building X86GenAsmWriter1.inc...   Building X86GenCallingConv.inc...   Building X86GenDAGISel.inc...   Building X86GenDisassemblerTables.inc...   Building X86GenEVEX2VEXTables.inc...   Building X86GenFastISel.inc...   Building X86GenGlobalISel.inc...   ... which costs me much time (>30min) on my slow system - and i don't understand why "AlwaysCreate" is used here - i only added one lib dependencie to an example and reverted it? now the totaly unrelated big one is build again it could be that faster systems do not suffer that much from this behavior but it still does not feel right

enough RAM, no swapping, just my 2 core CPU is not fast enough

result: Fibonacci was built without errors

after building i reopened llvm-build\LLVM.sln in VS2017 ... loading 273 projects and tested what happend on selecting "build solution" - to check what else happened to build now serveral cpp getting compiled, libs/exes getting linked - i think that is related to the X86CommonTableGen rebuild another >30min waiting to "finish building" the solution inside of the IDE

nearly enough RAM, started swapping on building lli.cpp :(, but get back to under 5GB Ram usage after some seconds, my 2 core CPU is still not fast enough

Otherwise, there might be some workarounds. E.g. Unload the "ZERO_CHECK" project from the IDE so it does not reconfigure (or just run cmake from outside the IDE before building). Or start the IDE from the Developer Command Prompt so the right environment variables are set.

will check that later - it just costs me way too much time to get to this point (Fibonacci from outside, finish build of solution inside IDE), currently nearly 2 hours :(

beside "i don't really know what im doing" and the short swapping problem the workflow/build optimization of the CMake scripts feels strange, not very optimal is that a windows/VStudio generator only effect (and no one is using that, or everyone got more cores/RAM?) or how does this usually work? other CMake based projects do not behave like this on my system

as a side note: i also got VS2010 and VS2015 installed on my build system

Am 21.09.2018 um 19:20 schrieb Michael Kruse:

I might try compiling your source from the VS's Developer Command Prompt:

cmake --build . --target Fibonacci Does this work? Otherwise, there might be some workarounds. E.g. Unload the "ZEROCHECK" project from the IDE so it does not reconfigure (or just run cmake from outside the IDE before building). Or start the IDE from the Developer Command Prompt so the right environment variables are set. Michael

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