HPX_DEBUG/CMAKE_BUILD_TYPE not correctly decoupled/consistently used.

[Neumann-A]

hpx/libs/core/config/include/hpx/config.hpp

Lines 277 to 296 in a7ea579

	#if !defined(HPX_WINDOWS)
	# if defined(HPX_DEBUG)
	# define HPX_MAKE_DLL_STRING(n) "lib" + n + "d" + HPX_SHARED_LIB_EXTENSION
	# else
	# define HPX_MAKE_DLL_STRING(n) "lib" + n + HPX_SHARED_LIB_EXTENSION
	# endif
	#elif defined(HPX_DEBUG)
	# define HPX_MAKE_DLL_STRING(n) (n) + "d" + HPX_SHARED_LIB_EXTENSION
	#else
	# define HPX_MAKE_DLL_STRING(n) (n) + HPX_SHARED_LIB_EXTENSION
	#endif
	#if defined(HPX_DEBUG)
	# define HPX_MANGLE_NAME(n) HPX_PP_CAT(n, d)
	# define HPX_MANGLE_STRING(n) (n) + "d"
	#else
	# define HPX_MANGLE_NAME(n) n
	# define HPX_MANGLE_STRING(n) n
	#endif

assumes HPX_DEBUG for name mangling.
(different issue: assumes fixed library prefixes and suffixes which can be easily changed by cmake variables. )

hpx/CMakeLists.txt

Lines 2191 to 2192 in a7ea579

	set(CMAKE_DEBUG_POSTFIX "d")
	set(HPX_DEBUG_POSTFIX "d")

Hardcodes d suffix dependent on CMAKE_BUILD_TYPE

hpx/cmake/HPX_CompilerFlagsTargets.cmake

Lines 18 to 25 in a7ea579

	# HPX_DEBUG must be set without a generator expression as it determines ABI
	# compatibility. Projects in Release mode using HPX in Debug mode must have
	# HPX_DEBUG set, and projects in Debug mode using HPX in Release mode must not
	# have HPX_DEBUG set. HPX_DEBUG must also not be set by projects using HPX.
	if(${CMAKE_BUILD_TYPE} STREQUAL "Debug")
	target_compile_definitions(hpx_private_flags INTERFACE HPX_DEBUG)
	target_compile_definitions(hpx_public_flags INTERFACE HPX_DEBUG)
	endif()

Tries to decouple HPX_DEBUG from CMAKE_BUILD_TYPE (which of course isn't correct if the above is done.)

Looking at that mess at least the third code fragment should be changed to

   target_compile_definitions(hpx_private_flags INTERFACE "$<$<CONFIG:DEBUG>:HPX_DEBUG>") 
   target_compile_definitions(hpx_public_flags INTERFACE "$<$<CONFIG:DEBUG>:HPX_DEBUG>") 

or the second fragment must be applied to all <CONFIG> suffixes.

[hkaiser]

@Neumann-A: Good catch! Thanks for the analysis.