[CMake] Building CLR project OR removing COMPILE_FLAGS

Thu Apr 7 10:02:40 EDT 2011

On 04/07/2011 02:33 PM, Neil MacMullen wrote:
> I'm a newcomer to cmake so if I'm missing something obvious please point it out.  Having said that, despite reading the online documentation and doing a fair amount of googling I haven't found a solution. 
> 
> 
> Specific Questions
> ====================
> 1) Is there a target/generator or some other configuration that will allow 'automatic' building of CLR targets with the appropriate compiler flags?
> 2) Is there a recipe for removing flags from COMPILE_FLAGS so I can build my own options?
> 3) Is CMAKE_CXX_FLAGS the correct variable to tweak for Visual Studio 2010 compilation flags ?  If so, can you suggest a reason why the recipe I'm using below isn't producing the desired results ?
> 
> 
> Background to Problem
> ======================
> 
> We have some C code which can be either compiled into an embedded target or built into an emulation of that target running under .Net on windows.  Cmake seems like it would be a good solution to allow us to maintain a single set of project configurations and we've already successfully converted the embedded target configuration to cmake.
> 
> For windows 7, when running under .net, there are a number of specific compiler flags that need to be used to correctly build the project...
> 
> /CLR - used to indicate that this is a CLR target
> /TP - used to indicate that '.c' files should be treated as c++
> /FUpathToDll - used to indicate that namespaces and unresolved references may be found within the specified dll
> 
> I've generated a minimal test project using 
>> cmake -G " Visual Studio 10 Win64" (Note cmake is 2.8.4)
> and have created a CMakeList.text that includes
> 
> cmake_minimum_required (VERSION 2.6)
> project (test)
> add_subdirectory("src")
> set_source_files_properties(src/main.c PROPERTIES COMPILE_FLAGS "/CLR /TP /FUotherstuff.dll")
> add_executable(test src/main.c)
> 
> There is a also an empty cmakelists.txt in the src subdirectory to keep cmake happy.
> 
> The problem is that when trying to build ALL_BUILDS, cmake's idea of which compiler flags to use is not compatible with the additional flags I'd like to use.  Here's some sample output. 
> 
> Note the error "cl : Command line error D8016: '/RTC1' and '/clr' command-line options are incompatible"
> 
> 
> -----------------------
> C:\work\cmaketest>msbuild ALL_BUILD.vcxproj
> Microsoft (R) Build Engine Version 4.0.30319.1
> [Microsoft .NET Framework, Version 4.0.30319.1]
> Copyright (C) Microsoft Corporation 2007. All rights reserved.
> 
> Build started 07/04/2011 13:06:03.
> Project "C:\work\cmaketest\ALL_BUILD.vcxproj" on node 1 (default targets).
> Project "C:\work\cmaketest\ALL_BUILD.vcxproj" (1) is building "C:\work\cmaketest\ZERO_CHECK.vcxproj" (2) on node 1 (default targets).
> InitializeBuildStatus:
>   Creating "Win32\Debug\ZERO_CHECK\ZERO_CHECK.unsuccessfulbuild" because "AlwaysCreate" was specified.
> CustomBuild:
>   All outputs are up-to-date.
> FinalizeBuildStatus:
>   Deleting file "Win32\Debug\ZERO_CHECK\ZERO_CHECK.unsuccessfulbuild".
>   Touching "Win32\Debug\ZERO_CHECK\ZERO_CHECK.lastbuildstate".
> Done Building Project "C:\work\cmaketest\ZERO_CHECK.vcxproj" (default targets).
> 
> Project "C:\work\cmaketest\ALL_BUILD.vcxproj" (1) is building "C:\work\cmaketest\test.vcxproj" (3) on node 1 (default targets).
> InitializeBuildStatus:
>   Touching "test.dir\Debug\test.unsuccessfulbuild".
> CustomBuild:
>   All outputs are up-to-date.
> ClCompile:
>   C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\bin\CL.exe /c /Zi /nologo /W3 /WX- /Od /Ob0 /Oy- /D WIN32 /D _WINDOWS /D _DEBUG /D "CMAKE_INTDIR=\"Debug\"" /D _MBCS /Gm- /RTC1 /MDd /GS /fp:precise /Zc:wchar_t /Zc:forScope /Fo"test.dir\Debug\\" /Fd"C:/work/cmaketest/Debug/test.pdb" /Gd /TP /FUotherstuff.dll /analyze- /errorReport:queue src\main.c  /CLR  /Zm1000
> cl : Command line error D8016: '/RTC1' and '/clr' command-line options are incompatible [C:\work\cmaketest\test.vcxproj]
> Done Building Project "C:\work\cmaketest\test.vcxproj" (default targets) -- FAILED.
> 
> Done Building Project "C:\work\cmaketest\ALL_BUILD.vcxproj" (default targets) -- FAILED.
> 
> 
> Build FAILED.
> 
> "C:\work\cmaketest\ALL_BUILD.vcxproj" (default target) (1) ->
> "C:\work\cmaketest\test.vcxproj" (default target) (3) ->
> (ClCompile target) ->
>   cl : Command line error D8016: '/RTC1' and '/clr' command-line options are incompatible [C:\work\cmaketest\test.vcxproj]
> 
>     0 Warning(s)
>     1 Error(s)
> 
> Time Elapsed 00:00:00.21
> ------------------------
> 
> This link: http://www.mail-archive.com/cmake@cmake.org/msg34975.html and this link http://www.cmake.org/pipermail/cmake/2010-June/037346.html suggest that modifying CMAKE_CXX_FLAGS will allow the removal of the conflicting flags.  Unfortunately I can't get this to work at all.  The following cmakelist.txt...
> ----
> cmake_minimum_required (VERSION 2.6)
> project (test)
> 
> STRING(REPLACE "/EHsc" "/EHa" CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS})
> STRING(REPLACE "/RTC1" "" CMAKE_CXX_FLAGS_DEBUG ${CMAKE_CXX_FLAGS_DEBUG})
> SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /clr")
> 
> add_subdirectory("src")
> add_executable(test src/main.c)
> ---
> 
> Still results in this clcompile step (note incorrect flags)
> 
> ClCompile:
>   C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\bin\x86_amd64\CL.exe /c /Zi /nologo /W3 /WX- /Od /Ob0 /D WIN32 /D _WINDOWS /D _DEBUG /D "CMAKE_INTDIR=\"Debug\"" /D _MBCS /Gm- /RTC1 /MDd /GS  /fp:precise /Zc:wchar_t /Zc:forScope /Fo"test.dir\Debug\\" /Fd"C:/work/cmaketest/Debug/test.pdb" /Gd /TC /errorReport:queue src\main.c  /Zm1000  main.c 
> 
> I've also tried likely permutations of the above, reordering of the step etc without any luck.
> 
>  Thanks in advance for any help you can offer,
> 
>   Neil

Usually, CMake has no idea that a ".c" file like src/main.c is to be
treated by a C++ compiler, so it applies the CMAKE_C_FLAGS[_<CONFIG>]
variables to the compilation. Thus, you probably need to tweak these
variables to suit your needs instead of the C++ ones. Moreover, note
that the non-configuration-specific CMAKE_<LANG>_FLAGS variables are
in effect for any configuration. As an alternative, you might change
the language associated with src/main.c to C++ by setting the file's
LANGUAGE source property accordingly. Two further recommendations:

- When setting source properties, always use full paths as it isn't
  documented if relative paths refer to the source directory or the
  build tree. In this regard, keep generated source files in mind.
- If there's nothing CMake can do for you in a directory, just do
  not enter it, i.e. no ADD_SUBDIRECTORY() command, instead of
  placing an empty CMakeLists.txt file therein.

For a consideration how to fully control compilation flags, see [1].

'hope that helps.

Regards,

Michael

[1] http://www.mail-archive.com/cmake@cmake.org/msg35548.html