CMake: prefer 'string(APPEND' over stammering 'set'

CMakeLists.txt

@@ -68,11 +68,11 @@ include(GetFilenameComponent) # overwrite CMake command
 include(CheckCompiler)
 include(Dependences)
 if(ZERO_TOLERANCE)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror -Wfatal-errors")
+    string(APPEND CMAKE_CXX_FLAGS " -Werror -Wfatal-errors")
 endif()
 if(BORNAGAIN_GUI)
     include(SearchQt)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DHAVE_QT=ON")
+    string(APPEND CMAKE_CXX_FLAGS " -DHAVE_QT=ON")
 endif()
 include(BornAgainConfiguration)
 include(GeneratePythonDocs)

Core/CMakeLists.txt

@@ -14,7 +14,7 @@ if((NOT Cerf_IS_CPP) AND (NOT WIN32)) # TEMPORARY
     list(APPEND source_files ${CMAKE_SOURCE_DIR}/ThirdParty/Core/cerf_wrapper/cerf_ptr.c)
 endif()
 if(${Cerf_IS_CPP})
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DCERF_AS_CPP=ON")
+    string(APPEND CMAKE_CXX_FLAGS " -DCERF_AS_CPP=ON")
 endif()
 
 
@@ -87,7 +87,7 @@ endif(BORNAGAIN_PYTHON)
 # --- making library ---
 
 if(WIN32)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DBA_CORE_BUILD_DLL")
+    string(APPEND CMAKE_CXX_FLAGS " -DBA_CORE_BUILD_DLL")
 endif()
 
 add_library(${lib} SHARED ${source_files})

Fit/CMakeLists.txt

@@ -81,7 +81,7 @@ endif(BORNAGAIN_PYTHON)
 # --- making library ---
 
 if(WIN32)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DBA_CORE_BUILD_DLL")
+    string(APPEND CMAKE_CXX_FLAGS " -DBA_CORE_BUILD_DLL")
 endif()
 
 add_library(${lib} SHARED ${source_files})

GUI/coregui/CMakeLists.txt

@@ -77,7 +77,7 @@ if(BORNAGAIN_CRASHHANDLER)
 endif()
 
 if(WIN32)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DBA_CORE_BUILD_DLL")
+    string(APPEND CMAKE_CXX_FLAGS " -DBA_CORE_BUILD_DLL")
 endif()
 
 

Tests/UnitTests/Numeric/CMakeLists.txt

@@ -3,7 +3,7 @@ include(GoogleTest) # provides gtest_discover_tests
 set(test UnitTestNumeric)
 
 if(MSVC)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DGTEST_LINKED_AS_SHARED_LIBRARY=1")
+    string(APPEND CMAKE_CXX_FLAGS " -DGTEST_LINKED_AS_SHARED_LIBRARY=1")
 endif()
 
 file(GLOB source_files "*.cpp" ${CMAKE_SOURCE_DIR}/Tests/GTestWrapper/TestAll.cpp)

cmake/extensions/CoverageFunction.cmake

@@ -38,13 +38,13 @@ else()
 endif()
 
 if(CMAKE_C_COMPILER_ID STREQUAL "GNU")
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -coverage")
+    string(APPEND CMAKE_C_FLAGS " -coverage")
 else()
     message(ERROR "C compiler is not GNU; don't know how to set code coverage flags!")
 endif()
 
 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -coverage")
+    string(APPEND CMAKE_CXX_FLAGS " -coverage")
 else()
     message(ERROR "CXX compiler is not GNU; don't know how to set code coverage flags!")
 endif()

cmake/extensions/DebugOptimization.cmake

@@ -17,13 +17,13 @@
 #
 
 if(CMAKE_C_COMPILER_ID STREQUAL "GNU")
-  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Og")
+  string(APPEND CMAKE_C_FLAGS " -Og")
 else()
   message(WARNING "C compiler is not GNU; debug optimization has no effect")
 endif()
 
 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Og")
+  string(APPEND CMAKE_CXX_FLAGS " -Og")
 else()
   message(WARNING "C compiler is not GNU; debug optimization has no effect")
 endif()

cmake/modules/BornAgainConfiguration.cmake

@@ -117,7 +117,7 @@ endif()
 configure_file(${CONFIGURABLES_DIR}/BAVersion.h.in  ${BUILD_INC_DIR}/BAVersion.h @ONLY)
 configure_file(${CONFIGURABLES_DIR}/BABuild.h.in  ${BUILD_INC_DIR}/BABuild.h @ONLY)
 configure_file(${CONFIGURABLES_DIR}/BATesting.h.in  ${BUILD_INC_DIR}/BATesting.h @ONLY)
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I${BUILD_INC_DIR}")
+string(APPEND CMAKE_CXX_FLAGS " -I${BUILD_INC_DIR}")
 
 configure_file(${CMAKE_SOURCE_DIR}/Examples/python/utils/plot_intensity_data.py
     ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/plot_intensity_data.py COPYONLY)

cmake/modules/CheckCompiler.cmake

@@ -32,11 +32,11 @@ message(STATUS "Build Type: ${CMAKE_BUILD_TYPE}")
 
 set(all_cxx_flags ${CMAKE_CXX_FLAGS})
 if(CMAKE_BUILD_TYPE STREQUAL "Release")
-    set(all_cxx_flags "${all_cxx_flags} ${CMAKE_CXX_FLAGS_RELEASE}")
+    string(APPEND all_cxx_flags " ${CMAKE_CXX_FLAGS_RELEASE}")
 elseif(CMAKE_BUILD_TYPE STREQUAL "Debug")
-    set(all_cxx_flags "${all_cxx_flags} ${CMAKE_CXX_FLAGS_DEBUG}")
+    string(APPEND all_cxx_flags " ${CMAKE_CXX_FLAGS_DEBUG}")
 elseif(CMAKE_BUILD_TYPE STREQUAL "RelWithDebInfo")
-    set(all_cxx_flags "${all_cxx_flags} ${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
+    string(APPEND all_cxx_flags " ${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
 endif()
 
 message(STATUS "Compiler Flags: ${all_cxx_flags}")

cmake/modules/SetUpLinux.cmake

@@ -19,6 +19,6 @@ set(CMAKE_C_FLAGS_RELWITHDEBINFO   "-O2 -g")
 set(CMAKE_C_FLAGS_RELEASE          "-O3")
 set(CMAKE_C_FLAGS_DEBUG            "-g")
 
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I${CMAKE_SOURCE_DIR}/Wrap -pipe ${BIT_ENVIRONMENT} -Wall -W -Woverloaded-virtual -Wno-unknown-pragmas -fPIC")
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pipe ${BIT_ENVIRONMENT} -Wall -W -fPIC")
+string(APPEND CMAKE_CXX_FLAGS " -I${CMAKE_SOURCE_DIR}/Wrap -pipe ${BIT_ENVIRONMENT} -Wall -W -Woverloaded-virtual -Wno-unknown-pragmas -fPIC")
+string(APPEND CMAKE_C_FLAGS " -pipe ${BIT_ENVIRONMENT} -Wall -W -fPIC")
 set(CMAKE_SHARED_LINKER_FLAGS "-Wl,--no-undefined")

cmake/modules/SetUpMacOS.cmake

@@ -21,16 +21,16 @@ if (CMAKE_SYSTEM_NAME MATCHES Darwin)
        MESSAGE(STATUS "Found a 64bit system")
        set(BORNAGAIN_ARCHITECTURE macosx64)
        SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS}")
-       SET(CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS} -m64")
-       SET(CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS} -m64")
-       SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -m64")
-       SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -m64")
-       SET(CMAKE_FORTRAN_FLAGS "${CMAKE_FORTRAN_FLAGS} -m64")
+       string(APPEND CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS " -m64")
+       string(APPEND CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS " -m64")
+       string(APPEND CMAKE_CXX_FLAGS " -m64")
+       string(APPEND CMAKE_C_FLAGS " -m64")
+       string(APPEND CMAKE_FORTRAN_FLAGS " -m64")
     else(${SYSCTL_OUTPUT} MATCHES 64)
        MESSAGE(STATUS "Found a 32bit system")
-       SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -m32")
-       SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -m32")
-       SET(CMAKE_FORTRAN_FLAGS "${CMAKE_FORTRAN_FLAGS} -m32")
+       string(APPEND CMAKE_CXX_FLAGS " -m32")
+       string(APPEND CMAKE_C_FLAGS " -m32")
+       string(APPEND CMAKE_FORTRAN_FLAGS " -m32")
     endif(${SYSCTL_OUTPUT} MATCHES 64)
   endif()
 
@@ -38,17 +38,17 @@ if (CMAKE_SYSTEM_NAME MATCHES Darwin)
      message(STATUS "Found GNU compiler collection")
      execute_process(COMMAND ${CMAKE_C_COMPILER} -dumpversion OUTPUT_VARIABLE GCC_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
 
-     SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pipe -W -Wall -Woverloaded-virtual -fsigned-char -fno-common")
-     SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pipe -W -Wall -fsigned-char -fno-common")
+     string(APPEND CMAKE_CXX_FLAGS " -pipe -W -Wall -Woverloaded-virtual -fsigned-char -fno-common")
+     string(APPEND CMAKE_C_FLAGS " -pipe -W -Wall -fsigned-char -fno-common")
      SET(CMAKE_Fortran_FLAGS "${CMAKE_FORTRAN_FLAGS} -std=legacy")
      SET(CINT_CXX_DEFINITIONS "-DG__REGEXP -DG__UNIX -DG__SHAREDLIB -DG__ROOT -DG__REDIRECTIO -DG__OSFDLL -DG__STD_EXCEPTION")
      SET(CINT_C_DEFINITIONS "-DG__REGEXP -DG__UNIX -DG__SHAREDLIB -DG__ROOT -DG__REDIRECTIO -DG__OSFDLL -DG__STD_EXCEPTION")
 
-     SET(CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS} -flat_namespace -single_module -undefined dynamic_lookup")
-     SET(CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS} -flat_namespace -single_module -undefined dynamic_lookup")
+     string(APPEND CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS " -flat_namespace -single_module -undefined dynamic_lookup")
+     string(APPEND CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS " -flat_namespace -single_module -undefined dynamic_lookup")
 
-     set(CMAKE_C_LINK_FLAGS "${CMAKE_C_LINK_FLAGS} -bind_at_load -m64")
-     set(CMAKE_CXX_LINK_FLAGS "${CMAKE_CXX_LINK_FLAGS} -bind_at_load -m64")
+     string(APPEND CMAKE_C_LINK_FLAGS " -bind_at_load -m64")
+     string(APPEND CMAKE_CXX_LINK_FLAGS " -bind_at_load -m64")
 
      # Select flags.
      set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2 -g")
@@ -73,17 +73,17 @@ if (CMAKE_SYSTEM_NAME MATCHES Darwin)
      message(STATUS "Found LLVM compiler collection")
      execute_process(COMMAND ${CMAKE_C_COMPILER} -dumpversion OUTPUT_VARIABLE GCC_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
 
-     SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pipe -W -Wall -Woverloaded-virtual -fsigned-char -fno-common")
-     SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pipe -W -Wall -fsigned-char -fno-common")
+     string(APPEND CMAKE_CXX_FLAGS " -pipe -W -Wall -Woverloaded-virtual -fsigned-char -fno-common")
+     string(APPEND CMAKE_C_FLAGS " -pipe -W -Wall -fsigned-char -fno-common")
 #     SET(CMAKE_Fortran_FLAGS "${CMAKE_FORTRAN_FLAGS} -std=legacy")
 #     SET(CINT_CXX_DEFINITIONS "-DG__REGEXP -DG__UNIX -DG__SHAREDLIB -DG__ROOT -DG__REDIRECTIO -DG__OSFDLL -DG__STD_EXCEPTION")
 #     SET(CINT_C_DEFINITIONS "-DG__REGEXP -DG__UNIX -DG__SHAREDLIB -DG__ROOT -DG__REDIRECTIO -DG__OSFDLL -DG__STD_EXCEPTION")
 
-     SET(CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS} -flat_namespace -single_module -undefined dynamic_lookup")
-     SET(CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS} -flat_namespace -single_module -undefined dynamic_lookup")
+     string(APPEND CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS " -flat_namespace -single_module -undefined dynamic_lookup")
+     string(APPEND CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS " -flat_namespace -single_module -undefined dynamic_lookup")
 
-     set(CMAKE_C_LINK_FLAGS "${CMAKE_C_LINK_FLAGS} -bind_at_load -m64")
-     set(CMAKE_CXX_LINK_FLAGS "${CMAKE_CXX_LINK_FLAGS} -bind_at_load -m64")
+     string(APPEND CMAKE_C_LINK_FLAGS " -bind_at_load -m64")
+     string(APPEND CMAKE_CXX_LINK_FLAGS " -bind_at_load -m64")
 
      # Select flags.
      set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2 -g")
@@ -106,7 +106,7 @@ if (CMAKE_SYSTEM_NAME MATCHES Darwin)
     MESSAGE(FATAL_ERROR "There is no setup for this compiler up to now. Don't know waht to do. Stop cmake at this point.")
   endif()
 
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I${CMAKE_SOURCE_DIR}/Wrap")
+  string(APPEND CMAKE_CXX_FLAGS " -I${CMAKE_SOURCE_DIR}/Wrap")
 
 else (CMAKE_SYSTEM_NAME MATCHES Darwin)
   MESSAGE(FATAL_ERROR "There is no setup for this this Apple system up to now. Don't know waht to do. Stop cmake at this point.")

cmake/modules/SetUpWindows.cmake

@@ -11,5 +11,5 @@ endif()
 add_definitions(-DEIGEN_DONT_ALIGN_STATICALLY=1)
 message(STATUS "Disabling static align for Eigen")
 
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /MP /D_USE_MATH_DEFINES /wd4005 /wd4244 -I${CMAKE_SOURCE_DIR}/Wrap -FIw32pragma.h")
-set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} /NODEFAULTLIB:libcmtd.lib")
+string(APPEND CMAKE_CXX_FLAGS " /MP /D_USE_MATH_DEFINES /wd4005 /wd4244 -I${CMAKE_SOURCE_DIR}/Wrap -FIw32pragma.h")
+string(APPEND CMAKE_SHARED_LINKER_FLAGS " /NODEFAULTLIB:libcmtd.lib")