[llvm-dev] Miscellaneous warnings in code using Visual Studio

[Paul C. Anagnostopoulos via llvm-dev]

When I build on Windows 7 with Visual Studio, I get various warnings that were ignored until I recently set 

LLVM_ENABLE_WERROR:BOOL=ON

One example is shown below. Should I take the time to hunt these down and fix them?


**********************************************************************
** Visual Studio 2019 Developer Command Prompt v16.8.1
** Copyright (c) 2020 Microsoft Corporation
**********************************************************************

D:\LLVM\build>build-targets.bat
        1 file(s) copied.
[363/1578] Building CXX object lib\CodeGen\...LLVMGlobalISel.dir\MachineIRBuilder.cpp.obj
FAILED: lib/CodeGen/GlobalISel/CMakeFiles/LLVMGlobalISel.dir/MachineIRBuilder.cpp.obj
C:\PROGRA~2\MIB055~1\2019\COMMUN~1\VC\Tools\MSVC\1428~1.293\bin\Hostx86\x86\cl.exe  /nolog
o /TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS
-D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_FILE_OFFSET_BITS=64 -D_HAS_EXCEPTI
ONS=0 -D_LARGEFILE_SOURCE -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE
-D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Ilib\CodeGen\Global
ISel -IC:\LLVM\llvm-project\llvm\lib\CodeGen\GlobalISel -Iinclude -IC:\LLVM\llvm-project\l
lvm\include /DWIN32 /D_WINDOWS   /WX /Zc:inline /Zc:__cplusplus /Zc:strictStrings /Oi /Zc:
rvalueCast /bigobj /W4 -wd4141 -wd4146 -wd4244 -wd4267 -wd4291 -wd4351 -wd4456 -wd4457 -wd
4458 -wd4459 -wd4503 -wd4624 -wd4722 -wd4100 -wd4127 -wd4512 -wd4505 -wd4610 -wd4510 -wd47
02 -wd4245 -wd4706 -wd4310 -wd4701 -wd4703 -wd4389 -wd4611 -wd4805 -wd4204 -wd4577 -wd4091
 -wd4592 -wd4319 -wd4709 -wd4324 -w14062 -we4238 /MDd /Zi /Ob0 /Od /RTC1  /EHs-c- /GR- -st
d:c++14 /showIncludes /Folib\CodeGen\GlobalISel\CMakeFiles\LLVMGlobalISel.dir\MachineIRBui
lder.cpp.obj /Fdlib\CodeGen\GlobalISel\CMakeFiles\LLVMGlobalISel.dir\LLVMGlobalISel.pdb /F
S -c C:\LLVM\llvm-project\llvm\lib\CodeGen\GlobalISel\MachineIRBuilder.cpp
C:\LLVM\llvm-project\llvm\lib\CodeGen\GlobalISel\MachineIRBuilder.cpp(657): error C2220: t
he following warning is treated as an error
C:\LLVM\llvm-project\llvm\lib\CodeGen\GlobalISel\MachineIRBuilder.cpp(657): warning C4018:
 '>=': signed/unsigned mismatch
[366/1578] Building CXX object lib\CodeGen\...CMakeFiles\LLVMGlobalISel.dir\Utils.cpp.obj
ninja: build stopped: subcommand failed.