[Buildroot] [PATCH 2/3] package/pkg-cmake.mk: don't unconditionally set CMAKE_CXX_COMPILER

[Yann E. MORIN <yann.morin.1998@free.fr>]

Fabrice, All,

On 2021-04-02 18:33 +0200, Fabrice Fontaine spake thusly:
> Don't unconditionally set CMAKE_CXX_COMPILER as it will raise a build
> failure on qpid-proton because "if the toolchain specifies a value for
> CMAKE_CXX_COMPILER, then CMake assumes the compiler works and goes
> straight ahead trying to use it":
> https://cmake.org/cmake/help/latest/module/CheckLanguage.html
> https://issues.apache.org/jira/browse/PROTON-2365
> 
> Fixes:
>  - http://autobuild.buildroot.org/results/05f344151100219c159ca4d466a453df96bf07fa
> 
> Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>

Applied to master, with the following changes:

  - rename placeholder

Thanks!

Regards,
Yann E. MORIN.

> ---
>  package/pkg-cmake.mk                |  1 +
>  support/misc/toolchainfile.cmake.in | 10 ++++++----
>  2 files changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/package/pkg-cmake.mk b/package/pkg-cmake.mk
> index c001051002..53e6fb81f2 100644
> --- a/package/pkg-cmake.mk
> +++ b/package/pkg-cmake.mk
> @@ -264,6 +264,7 @@ define TOOLCHAIN_CMAKE_INSTALL_FILES
>  		-e 's#@@TARGET_CXX@@#$(subst $(HOST_DIR)/,,$(call qstrip,$(TARGET_CXX)))#' \
>  		-e 's#@@TARGET_FC@@#$(subst $(HOST_DIR)/,,$(call qstrip,$(TARGET_FC)))#' \
>  		-e 's#@@CMAKE_SYSTEM_PROCESSOR@@#$(call qstrip,$(CMAKE_SYSTEM_PROCESSOR))#' \
> +		-e 's#@@BR2_INSTALL_LIBSTDCPP@@#$(if $(BR2_INSTALL_LIBSTDCPP),1,0)#' \
>  		-e 's#@@TOOLCHAIN_HAS_FORTRAN@@#$(if $(BR2_TOOLCHAIN_HAS_FORTRAN),1,0)#' \
>  		-e 's#@@CMAKE_BUILD_TYPE@@#$(if $(BR2_ENABLE_DEBUG),Debug,Release)#' \
>  		$(TOPDIR)/support/misc/toolchainfile.cmake.in \
> diff --git a/support/misc/toolchainfile.cmake.in b/support/misc/toolchainfile.cmake.in
> index b25031a656..c2318f9587 100644
> --- a/support/misc/toolchainfile.cmake.in
> +++ b/support/misc/toolchainfile.cmake.in
> @@ -29,9 +29,7 @@ set(CMAKE_SYSTEM_PROCESSOR @@CMAKE_SYSTEM_PROCESSOR@@)
>  #   if the project forces some of these flag variables, Buildroot is
>  #   screwed up and there is nothing Buildroot can do about that :(
>  set(CMAKE_C_FLAGS_DEBUG "" CACHE STRING "Debug CFLAGS")
> -set(CMAKE_CXX_FLAGS_DEBUG "" CACHE STRING "Debug CXXFLAGS")
>  set(CMAKE_C_FLAGS_RELEASE " -DNDEBUG" CACHE STRING "Release CFLAGS")
> -set(CMAKE_CXX_FLAGS_RELEASE " -DNDEBUG" CACHE STRING "Release CXXFLAGS")
>  
>  # Build type from the Buildroot configuration
>  set(CMAKE_BUILD_TYPE @@CMAKE_BUILD_TYPE@@ CACHE STRING "Buildroot build configuration")
> @@ -44,7 +42,6 @@ set(CMAKE_BUILD_TYPE @@CMAKE_BUILD_TYPE@@ CACHE STRING "Buildroot build configur
>  # * and make sure the project's CMake code extends them like this if needed:
>  #     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Dsome_definitions")
>  set(CMAKE_C_FLAGS "@@TARGET_CFLAGS@@" CACHE STRING "Buildroot CFLAGS")
> -set(CMAKE_CXX_FLAGS "@@TARGET_CXXFLAGS@@" CACHE STRING "Buildroot CXXFLAGS")
>  set(CMAKE_EXE_LINKER_FLAGS "@@TARGET_LDFLAGS@@" CACHE STRING "Buildroot LDFLAGS for executables")
>  set(CMAKE_SHARED_LINKER_FLAGS "@@TARGET_LDFLAGS@@" CACHE STRING "Buildroot LDFLAGS for shared libraries")
>  set(CMAKE_MODULE_LINKER_FLAGS "@@TARGET_LDFLAGS@@" CACHE STRING "Buildroot LDFLAGS for module libraries")
> @@ -62,7 +59,12 @@ set(ENV{PKG_CONFIG_SYSROOT_DIR} "${RELOCATED_HOST_DIR}/@@STAGING_SUBDIR@@")
>  
>  # This toolchain file can be used both inside and outside Buildroot.
>  set(CMAKE_C_COMPILER "${RELOCATED_HOST_DIR}/@@TARGET_CC@@")
> -set(CMAKE_CXX_COMPILER "${RELOCATED_HOST_DIR}/@@TARGET_CXX@@")
> +if(@@BR2_INSTALL_LIBSTDCPP@@)
> +  set(CMAKE_CXX_FLAGS_DEBUG "" CACHE STRING "Debug CXXFLAGS")
> +  set(CMAKE_CXX_FLAGS_RELEASE " -DNDEBUG" CACHE STRING "Release CXXFLAGS")
> +  set(CMAKE_CXX_FLAGS "@@TARGET_CXXFLAGS@@" CACHE STRING "Buildroot CXXFLAGS")
> +  set(CMAKE_CXX_COMPILER "${RELOCATED_HOST_DIR}/@@TARGET_CXX@@")
> +endif()
>  if(@@TOOLCHAIN_HAS_FORTRAN@@)
>    set(CMAKE_Fortran_FLAGS_DEBUG "" CACHE STRING "Debug Fortran FLAGS")
>    set(CMAKE_Fortran_FLAGS_RELEASE " -DNDEBUG" CACHE STRING "Release Fortran FLAGS")
> -- 
> 2.30.2
> 
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

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