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According to tc-tp-tc-tp-specify-source-file-type specifying /Tc filename on the command line will override the /TP global option.
IntelliSense in a Visual Studio 2019 Makefile project assumes C++ but my files are C
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Renishug
1
Reputation point
Visual Studio 2019, V16.11.4
If I create a Makefile project, then add a C file, say main.c, to it, IntelliSense teats that file as a C++ file, not a C file, which is leading to IntelliSense squiggles that really should not be there.
I can tell that the file is being treated as C++ because if I enable Diagnostic Logging, with Level 5 and Filter 8, the output is:
<9448> [IntelliSense] command line options:
/c
/W1
/WX-
/DWIN32
/D_DEBUG
/EHsc
/MDd
/fp:precise
/Zc:wchar_t
/Zc:forScope
/ifcOutputDebug\
/FoDebug\
/Gd
/errorReport:prompt
/TP
/IC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\include
/IC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\atlmfc\include
/IC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Auxiliary\VS\include
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\ucrt
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\um
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\shared
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\winrt
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\cppwinrt
/IC:\Program Files (x86)\Windows Kits\NETFXSDK\4.8\Include\um
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\atlmfc\lib\x86
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\lib\x86
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\lib\x86
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\atlmfc\lib\x86
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Auxiliary\VS\lib\x86
/AIC:\Program Files (x86)\Windows Kits\10\lib\10.0.18362.0\ucrt\x86
/AIC:\Program Files (x86)\Windows Kits\10\lib\10.0.18362.0\um\x86
/AIC:\Program Files (x86)\Windows Kits\NETFXSDK\4.8\lib\um\x86
/BCDC:\Users\xxxxxxxx\source\repos\MakefileProjectTest
C:\USERS\xxxxxxxx\SOURCE\REPOS\MAKEFILEPROJECTTEST\MAIN.C
/AutoPCHC:\Users\xxxxxxxx\source\repos\MakefileProjectTest.vs\MakefileProjectTest\v16\ipch\AutoPCH\c899e3138a898b7c
Key in these command line options is "/TP", which means 'treat all files as C++'.
If I open the project Properties, go to the NMake Configuration Property, and add /TC /std:c11 to the "Additional Options" entry for IntelliSense, then the above becomes,
<9448> [IntelliSense] command line options:
/c
/W1
/WX-
/DWIN32
/D_DEBUG
/EHsc
/MDd
/fp:precise
/Zc:wchar_t
/Zc:forScope
/ifcOutputDebug\
/FoDebug\
/Gd
/errorReport:prompt
/TC
/std:c11
/TP
/IC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\include
/IC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\atlmfc\include
/IC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Auxiliary\VS\include
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\ucrt
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\um
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\shared
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\winrt
/IC:\Program Files (x86)\Windows Kits\10\Include\10.0.18362.0\cppwinrt
/IC:\Program Files (x86)\Windows Kits\NETFXSDK\4.8\Include\um
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\atlmfc\lib\x86
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\lib\x86
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\lib\x86
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\atlmfc\lib\x86
/AIC:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Auxiliary\VS\lib\x86
/AIC:\Program Files (x86)\Windows Kits\10\lib\10.0.18362.0\ucrt\x86
/AIC:\Program Files (x86)\Windows Kits\10\lib\10.0.18362.0\um\x86
/AIC:\Program Files (x86)\Windows Kits\NETFXSDK\4.8\lib\um\x86
/BCDC:\Users\xxxxxxxx\source\repos\MakefileProjectTest
C:\USERS\xxxxxxxx\SOURCE\REPOS\MAKEFILEPROJECTTEST\MAIN.C
/AutoPCHC:\Users\xxxxxxxx\source\repos\MakefileProjectTest.vs\MakefileProjectTest\v16\ipch\AutoPCH\c899e3138a898b7c
The "/TC /std:c11" has appeared, as expected, but the "/TP" is still there and appears to 'win'. A keyword of C11, _Noreturn, is being given a squiggly when I use it (correctly) in main.c. I would like to get rid of the "/TP" command line option but it is being added behind the scenes. Is there a way for me to be able to alter this?
Developer technologies | Visual Studio | Other
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PengGe-MSFT 3,381 Reputation points2021-10-18T09:36:33.177+00:00 Hi, @Renishug
I suggest you can start a new thread and report this issue to VS Product Team in our Developer Community with some reproduced or detailed information. if you do report this issue, please share the link here, other forum members who are interested or meet the same or similar issue can go to vote for this thread. -
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1 answer
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RLWA32 49,666 Reputation points2021-10-14T13:26:39.653+00:00 -
Renishug 1 Reputation point
2021-10-15T08:22:53.06+00:00 Many thanks for taking the trouble to respond. Unfortunately, I am wanting IntelliSense to work properly over the whole of my codebase, which is made up entirely of C files.
Out of interest, I specified both /TP and /Tcmain.c in a normal project (as opposed to a Makefile project) and main.c was compiled as C++, so /Tc was not overriding /TP. Using Detailed for the 'MSBuild project build output verbosity' the actual command line showed both options, with the order of them being /TP then /Tcmain.c. order-of-cl-options says "If CL encounters conflicting options, it uses the rightmost option", so on two counts /Tcmain.c should have been respected over /TP.
I also tried adding /Tcmain.c on my 'toy' Makefile project and seeing if it sorted out the IntelliSense issue that I am having, but it did not.
So /Tc turns out not to be a workaround for the issue that I am having.
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RLWA32 49,666 Reputation points
2021-10-15T09:22:16.307+00:00 Sounds like you found a bug that might be worth reporting.
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RLWA32 49,666 Reputation points
2021-10-19T08:50:31.863+00:00 Thanks for posting back. I upvoted the issue at developer community.
A few more observations. Following the steps in the reported issue I reproduced the problem as described. Then, instead of adding /Tc main.c as an additional command line parameter I set the project property for the main.c source module to "Compile as C". After making that change instead the project built and Intellisense showed no errors. However, closer examination of the command line used by the compiler for main.c showed that it DID NOT use the /Tc option. Instead the log file for the CL command showed that the command line did not contain /TP but instead used /TC. So although it built successfully it was not a valid test of the /Tc option in the IDE.
Then I moved to a Developer command prompt. From the command line, the compiler seemed to accept the /Tc option.
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