Lots of fixes regarding duplicate command line flags as well as letting CMake handle versioning itself without the toolchain intervening.

Author: Alexander Widerberg

example/example-app/example-lib/lib/libexample.a

@@ -2,6 +2,8 @@ cmake_minimum_required (VERSION 3.2)
 project (example-ios C CXX)
 enable_testing()
 
+MESSAGE( STATUS "CMAKE_CXX_FLAGS: " ${CMAKE_CXX_FLAGS} )
+
 # Add some sanitary checks that the toolchain is actually working!
 include(CheckCXXSymbolExists)
 check_cxx_symbol_exists(kqueue sys/event.h HAVE_KQUEUE)

example/example-lib/CMakeLists.txt

@@ -133,7 +133,6 @@ set(USED_CMAKE_GENERATOR "${CMAKE_GENERATOR}" CACHE STRING "Expose CMAKE_GENERAT
 
 if(${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.14")
   set(MODERN_CMAKE YES)
-  message(STATUS "Merging integrated CMake 3.14+ iOS,tvOS,watchOS,macOS toolchain(s) with this toolchain!")
 endif()
 
 # Get the Xcode version being used.
@@ -143,7 +142,6 @@ execute_process(COMMAND xcodebuild -version
   OUTPUT_STRIP_TRAILING_WHITESPACE)
 string(REGEX MATCH "Xcode [0-9\\.]+" XCODE_VERSION "${XCODE_VERSION}")
 string(REGEX REPLACE "Xcode ([0-9\\.]+)" "\\1" XCODE_VERSION "${XCODE_VERSION}")
-message(STATUS "Building with Xcode version: ${XCODE_VERSION}")
 
 ######## ALIASES (DEPRECATION WARNINGS)
 
@@ -304,7 +302,6 @@ elseif(PLATFORM_INT STREQUAL "SIMULATOR_WATCHOS")
 else()
   message(FATAL_ERROR "Invalid PLATFORM: ${PLATFORM_INT}")
 endif()
-message(STATUS "Configuring ${SDK_NAME} build for platform: ${PLATFORM_INT}, architecture(s): ${ARCHS}")
 
 if(MODERN_CMAKE AND PLATFORM_INT MATCHES ".*COMBINED" AND NOT USED_CMAKE_GENERATOR MATCHES "Xcode")
   message(FATAL_ERROR "The COMBINED options only work with Xcode generator, -G Xcode")
@@ -322,18 +319,15 @@ if (NOT DEFINED CMAKE_OSX_SYSROOT_INT AND NOT DEFINED CMAKE_OSX_SYSROOT)
   "and see if that fixes the problem for you.")
   message(FATAL_ERROR "Invalid CMAKE_OSX_SYSROOT: ${CMAKE_OSX_SYSROOT} "
   "does not exist.")
-elseif(DEFINED CMAKE_OSX_SYSROOT)
-  message(STATUS "Using SDK: ${CMAKE_OSX_SYSROOT} for platform: ${PLATFORM_INT} when checking compatibility")
 elseif(DEFINED CMAKE_OSX_SYSROOT_INT)
-   message(STATUS "Using SDK: ${CMAKE_OSX_SYSROOT_INT} for platform: ${PLATFORM_INT}")
    set(CMAKE_OSX_SYSROOT "${CMAKE_OSX_SYSROOT_INT}" CACHE INTERNAL "")
 endif()
 
 # Set Xcode property for SDKROOT as well if Xcode generator is used
 if(USED_CMAKE_GENERATOR MATCHES "Xcode")
   set(CMAKE_OSX_SYSROOT "${SDK_NAME}" CACHE INTERNAL "")
   if(NOT DEFINED CMAKE_XCODE_ATTRIBUTE_DEVELOPMENT_TEAM)
-    set(CMAKE_XCODE_ATTRIBUTE_DEVELOPMENT_TEAM 123456789A CACHE INTERNAL "")
+    set(CMAKE_XCODE_ATTRIBUTE_DEVELOPMENT_TEAM "123456789A" CACHE INTERNAL "")
   endif()
 endif()
 
@@ -350,6 +344,7 @@ if(NOT DEFINED DEPLOYMENT_TARGET)
   endif()
   message(STATUS "Using the default min-version since DEPLOYMENT_TARGET not provided!")
 endif()
+
 # Use bitcode or not
 if(NOT DEFINED ENABLE_BITCODE AND NOT ARCHS MATCHES "((^|;|, )(i386|x86_64))+")
   # Unless specified, enable bitcode support by default
@@ -435,7 +430,6 @@ if(NOT CMAKE_INSTALL_NAME_TOOL)
       ERROR_QUIET
       OUTPUT_STRIP_TRAILING_WHITESPACE)
   set(CMAKE_INSTALL_NAME_TOOL ${CMAKE_INSTALL_NAME_TOOL_INT} CACHE STRING "" ${FORCE_CACHE})
-  message(STATUS "Using install_name_tool: ${CMAKE_INSTALL_NAME_TOOL}")
 endif()
 # Get the version of Darwin (OS X) of the host.
 execute_process(COMMAND uname -r
@@ -454,7 +448,7 @@ if(MODERN_CMAKE)
   endif()
   # Provide flags for a combined FAT library build on newer CMake versions
   if(PLATFORM_INT MATCHES ".*COMBINED")
-    set(CMAKE_XCODE_ATTRIBUTE_ONLY_ACTIVE_ARCH NO CACHE INTERNAL "" ${FORCE_CACHE})
+    set(CMAKE_XCODE_ATTRIBUTE_ONLY_ACTIVE_ARCH "NO" CACHE INTERNAL "" ${FORCE_CACHE})
     set(CMAKE_IOS_INSTALL_COMBINED YES CACHE INTERNAL "" ${FORCE_CACHE})
     message(STATUS "Will combine built (static) artifacts into FAT lib...")
   endif()
@@ -504,110 +498,140 @@ if(ARCHS MATCHES "((^|;|, )(arm64|arm64e|x86_64))+")
   else()
     set(CMAKE_SYSTEM_PROCESSOR "x86_64")
   endif()
-  message(STATUS "Using a data_ptr size of 8")
 else()
   set(CMAKE_C_SIZEOF_DATA_PTR 4)
   set(CMAKE_CXX_SIZEOF_DATA_PTR 4)
   set(CMAKE_SYSTEM_PROCESSOR "arm")
-  message(STATUS "Using a data_ptr size of 4")
 endif()
 
-message(STATUS "Building for minimum ${SDK_NAME} version: ${DEPLOYMENT_TARGET}"
-               " (SDK version: ${SDK_VERSION})")
 # Note that only Xcode 7+ supports the newer more specific:
 # -m${SDK_NAME}-version-min flags, older versions of Xcode use:
 # -m(ios/ios-simulator)-version-min instead.
-if(PLATFORM_INT STREQUAL "OS" OR PLATFORM_INT STREQUAL "OS64")
-  if(XCODE_VERSION VERSION_LESS 7.0)
+if(${CMAKE_VERSION} VERSION_LESS "3.11")
+  if(PLATFORM_INT STREQUAL "OS" OR PLATFORM_INT STREQUAL "OS64")
+    if(XCODE_VERSION VERSION_LESS 7.0)
+      set(SDK_NAME_VERSION_FLAGS
+        "-mios-version-min=${DEPLOYMENT_TARGET}")
+    else()
+      # Xcode 7.0+ uses flags we can build directly from SDK_NAME.
+      set(SDK_NAME_VERSION_FLAGS
+        "-m${SDK_NAME}-version-min=${DEPLOYMENT_TARGET}")
+    endif()
+  elseif(PLATFORM_INT STREQUAL "TVOS")
     set(SDK_NAME_VERSION_FLAGS
-      "-mios-version-min=${DEPLOYMENT_TARGET}")
+      "-mtvos-version-min=${DEPLOYMENT_TARGET}")
+  elseif(PLATFORM_INT STREQUAL "SIMULATOR_TVOS")
+    set(SDK_NAME_VERSION_FLAGS
+      "-mtvos-simulator-version-min=${DEPLOYMENT_TARGET}")
+  elseif(PLATFORM_INT STREQUAL "WATCHOS")
+    set(SDK_NAME_VERSION_FLAGS
+      "-mwatchos-version-min=${DEPLOYMENT_TARGET}")
+  elseif(PLATFORM_INT STREQUAL "SIMULATOR_WATCHOS")
+    set(SDK_NAME_VERSION_FLAGS
+      "-mwatchos-simulator-version-min=${DEPLOYMENT_TARGET}")
   else()
-    # Xcode 7.0+ uses flags we can build directly from SDK_NAME.
+    # SIMULATOR or SIMULATOR64 both use -mios-simulator-version-min.
     set(SDK_NAME_VERSION_FLAGS
-      "-m${SDK_NAME}-version-min=${DEPLOYMENT_TARGET}")
+      "-mios-simulator-version-min=${DEPLOYMENT_TARGET}")
   endif()
-elseif(PLATFORM_INT STREQUAL "TVOS")
-  set(SDK_NAME_VERSION_FLAGS
-    "-mtvos-version-min=${DEPLOYMENT_TARGET}")
-elseif(PLATFORM_INT STREQUAL "SIMULATOR_TVOS")
-  set(SDK_NAME_VERSION_FLAGS
-    "-mtvos-simulator-version-min=${DEPLOYMENT_TARGET}")
-elseif(PLATFORM_INT STREQUAL "WATCHOS")
-  set(SDK_NAME_VERSION_FLAGS
-    "-mwatchos-version-min=${DEPLOYMENT_TARGET}")
-elseif(PLATFORM_INT STREQUAL "SIMULATOR_WATCHOS")
-  set(SDK_NAME_VERSION_FLAGS
-    "-mwatchos-simulator-version-min=${DEPLOYMENT_TARGET}")
 else()
-  # SIMULATOR or SIMULATOR64 both use -mios-simulator-version-min.
-  set(SDK_NAME_VERSION_FLAGS
-    "-mios-simulator-version-min=${DEPLOYMENT_TARGET}")
+  # Newer versions of CMake sets the version min flags correctly
+  set(CMAKE_OSX_DEPLOYMENT_TARGET ${DEPLOYMENT_TARGET} CACHE STRING
+      "Set CMake deployment target" ${FORCE_CACHE})
 endif()
-message(STATUS "Version flags set to: ${SDK_NAME_VERSION_FLAGS}")
-set(CMAKE_OSX_DEPLOYMENT_TARGET ${DEPLOYMENT_TARGET} CACHE STRING
-    "Set CMake deployment target" ${FORCE_CACHE})
+
 
 if(ENABLE_BITCODE_INT)
   set(BITCODE "-fembed-bitcode")
-  set(CMAKE_XCODE_ATTRIBUTE_BITCODE_GENERATION_MODE bitcode CACHE INTERNAL "")
-  message(STATUS "Enabling bitcode support.")
+  set(CMAKE_XCODE_ATTRIBUTE_BITCODE_GENERATION_MODE "bitcode" CACHE INTERNAL "")
+  set(CMAKE_XCODE_ATTRIBUTE_ENABLE_BITCODE "YES" CACHE INTERNAL "")
 else()
   set(BITCODE "")
-  set(CMAKE_XCODE_ATTRIBUTE_ENABLE_BITCODE NO CACHE INTERNAL "")
-  message(STATUS "Disabling bitcode support.")
+  set(CMAKE_XCODE_ATTRIBUTE_ENABLE_BITCODE "NO" CACHE INTERNAL "")
 endif()
 
 if(ENABLE_ARC_INT)
   set(FOBJC_ARC "-fobjc-arc")
-  set(CMAKE_XCODE_ATTRIBUTE_CLANG_ENABLE_OBJC_ARC YES CACHE INTERNAL "")
-  message(STATUS "Enabling ARC support.")
+  set(CMAKE_XCODE_ATTRIBUTE_CLANG_ENABLE_OBJC_ARC "YES" CACHE INTERNAL "")
 else()
   set(FOBJC_ARC "-fno-objc-arc")
-  set(CMAKE_XCODE_ATTRIBUTE_CLANG_ENABLE_OBJC_ARC NO CACHE INTERNAL "")
-  message(STATUS "Disabling ARC support.")
+  set(CMAKE_XCODE_ATTRIBUTE_CLANG_ENABLE_OBJC_ARC "NO" CACHE INTERNAL "")
 endif()
 
 if(NOT ENABLE_VISIBILITY_INT)
   set(VISIBILITY "-fvisibility=hidden")
-  set(CMAKE_XCODE_ATTRIBUTE_GCC_SYMBOLS_PRIVATE_EXTERN YES CACHE INTERNAL "")
-  message(STATUS "Hiding symbols (-fvisibility=hidden).")
+  set(CMAKE_XCODE_ATTRIBUTE_GCC_SYMBOLS_PRIVATE_EXTERN "YES" CACHE INTERNAL "")
 else()
   set(VISIBILITY "")
-  set(CMAKE_XCODE_ATTRIBUTE_GCC_SYMBOLS_PRIVATE_EXTERN NO CACHE INTERNAL "")
+  set(CMAKE_XCODE_ATTRIBUTE_GCC_SYMBOLS_PRIVATE_EXTERN "NO" CACHE INTERNAL "")
 endif()
 
-#Check if Xcode generator is used, since that will handle these flags automagically
-if(USED_CMAKE_GENERATOR MATCHES "Xcode")
-  message(STATUS "Not setting any manual command-line buildflags, since Xcode is selected as generator.")
-else()
-  set(CMAKE_C_FLAGS
-  "${SDK_NAME_VERSION_FLAGS} ${BITCODE} -fobjc-abi-version=2 ${FOBJC_ARC} ${CMAKE_C_FLAGS}")
-  # Hidden visibilty is required for C++ on iOS.
-  set(CMAKE_CXX_FLAGS
-  "${SDK_NAME_VERSION_FLAGS} ${BITCODE} ${VISIBILITY} -fvisibility-inlines-hidden -fobjc-abi-version=2 ${FOBJC_ARC} ${CMAKE_CXX_FLAGS}")
-  set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS} -O0 -g ${CMAKE_CXX_FLAGS_DEBUG}")
-  set(CMAKE_CXX_FLAGS_MINSIZEREL "${CMAKE_CXX_FLAGS} -DNDEBUG -Os -ffast-math ${CMAKE_CXX_FLAGS_MINSIZEREL}")
-  set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS} -DNDEBUG -O2 -g -ffast-math ${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
-  set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS} -DNDEBUG -O3 -ffast-math ${CMAKE_CXX_FLAGS_RELEASE}")
-  set(CMAKE_C_LINK_FLAGS "${SDK_NAME_VERSION_FLAGS} -Wl,-search_paths_first ${CMAKE_C_LINK_FLAGS}")
-  set(CMAKE_CXX_LINK_FLAGS "${SDK_NAME_VERSION_FLAGS}  -Wl,-search_paths_first ${CMAKE_CXX_LINK_FLAGS}")
-  SET(CMAKE_ASM_FLAGS "${CFLAGS} -x assembler-with-cpp")
-
-  # In order to ensure that the updated compiler flags are used in try_compile()
-  # tests, we have to forcibly set them in the CMake cache, not merely set them
-  # in the local scope.
-  list(APPEND VARS_TO_FORCE_IN_CACHE
-    CMAKE_C_FLAGS
-    CMAKE_CXX_FLAGS
-    CMAKE_CXX_FLAGS_DEBUG
-    CMAKE_CXX_FLAGS_RELWITHDEBINFO
-    CMAKE_CXX_FLAGS_MINSIZEREL
-    CMAKE_CXX_FLAGS_RELEASE
-    CMAKE_C_LINK_FLAGS
-    CMAKE_CXX_LINK_FLAGS)
-  foreach(VAR_TO_FORCE ${VARS_TO_FORCE_IN_CACHE})
-    set(${VAR_TO_FORCE} "${${VAR_TO_FORCE}}" CACHE STRING "")
-  endforeach()
+if(NOT IOS_TOOLCHAIN_HAS_RUN)
+  #Check if Xcode generator is used, since that will handle these flags automagically
+  if(USED_CMAKE_GENERATOR MATCHES "Xcode")
+    message(STATUS "Not setting any manual command-line buildflags, since Xcode is selected as generator.")
+  else()
+    set(CMAKE_C_FLAGS
+    "${SDK_NAME_VERSION_FLAGS} ${BITCODE} -fobjc-abi-version=2 ${FOBJC_ARC} ${CMAKE_C_FLAGS}")
+    # Hidden visibilty is required for C++ on iOS.
+    set(CMAKE_CXX_FLAGS
+    "${SDK_NAME_VERSION_FLAGS} ${BITCODE} ${VISIBILITY} -fvisibility-inlines-hidden -fobjc-abi-version=2 ${FOBJC_ARC} ${CMAKE_CXX_FLAGS}")
+    set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS} -O0 -g ${CMAKE_CXX_FLAGS_DEBUG}")
+    set(CMAKE_CXX_FLAGS_MINSIZEREL "${CMAKE_CXX_FLAGS} -DNDEBUG -Os -ffast-math ${CMAKE_CXX_FLAGS_MINSIZEREL}")
+    set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS} -DNDEBUG -O2 -g -ffast-math ${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
+    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS} -DNDEBUG -O3 -ffast-math ${CMAKE_CXX_FLAGS_RELEASE}")
+    set(CMAKE_C_LINK_FLAGS "${SDK_NAME_VERSION_FLAGS} -Wl,-search_paths_first ${CMAKE_C_LINK_FLAGS}")
+    set(CMAKE_CXX_LINK_FLAGS "${SDK_NAME_VERSION_FLAGS}  -Wl,-search_paths_first ${CMAKE_CXX_LINK_FLAGS}")
+    set(CMAKE_ASM_FLAGS "${CFLAGS} -x assembler-with-cpp")
+
+    # In order to ensure that the updated compiler flags are used in try_compile()
+    # tests, we have to forcibly set them in the CMake cache, not merely set them
+    # in the local scope.
+    set(VARS_TO_FORCE_IN_CACHE
+      CMAKE_C_FLAGS
+      CMAKE_CXX_FLAGS
+      CMAKE_CXX_FLAGS_DEBUG
+      CMAKE_CXX_FLAGS_RELWITHDEBINFO
+      CMAKE_CXX_FLAGS_MINSIZEREL
+      CMAKE_CXX_FLAGS_RELEASE
+      CMAKE_C_LINK_FLAGS
+      CMAKE_CXX_LINK_FLAGS)
+    foreach(VAR_TO_FORCE ${VARS_TO_FORCE_IN_CACHE})
+      set(${VAR_TO_FORCE} "${${VAR_TO_FORCE}}" CACHE STRING "" ${FORCE_CACHE})
+    endforeach()
+  endif()
+
+  ## Print status messages to inform of the current state
+  message(STATUS "Configuring ${SDK_NAME} build for platform: ${PLATFORM_INT}, architecture(s): ${ARCHS}")
+  message(STATUS "Using SDK: ${CMAKE_OSX_SYSROOT_INT}")
+  message(STATUS "Using minimum deployment version: ${DEPLOYMENT_TARGET}"
+      " (SDK version: ${SDK_VERSION})")
+  if(MODERN_CMAKE)
+    message(STATUS "Merging integrated CMake 3.14+ iOS,tvOS,watchOS,macOS toolchain(s) with this toolchain!")
+  endif()
+  if(USED_CMAKE_GENERATOR MATCHES "Xcode")
+    message(STATUS "Using Xcode version: ${XCODE_VERSION}")
+  endif()
+  if(DEFINED SDK_NAME_VERSION_FLAGS)
+    message(STATUS "Using version flags: ${SDK_NAME_VERSION_FLAGS}")
+  endif()
+  message(STATUS "Using a data_ptr size of: ${CMAKE_CXX_SIZEOF_DATA_PTR}")
+  message(STATUS "Using install_name_tool: ${CMAKE_INSTALL_NAME_TOOL}")
+  if(ENABLE_BITCODE_INT)
+    message(STATUS "Enabling bitcode support.")
+  else()
+    message(STATUS "Disabling bitcode support.")
+  endif()
+
+  if(ENABLE_ARC_INT)
+    message(STATUS "Enabling ARC support.")
+  else()
+    message(STATUS "Disabling ARC support.")
+  endif()
+
+  if(NOT ENABLE_VISIBILITY_INT)
+    message(STATUS "Hiding symbols (-fvisibility=hidden).")
+  endif()
 endif()
 
 set(CMAKE_PLATFORM_HAS_INSTALLNAME 1)
@@ -630,6 +654,8 @@ set(CMAKE_FRAMEWORK_PATH
   ${CMAKE_OSX_SYSROOT_INT}/System/Library/Frameworks
   ${CMAKE_FRAMEWORK_PATH} CACHE STRING "Frameworks search paths" ${FORCE_CACHE})
 
+set(IOS_TOOLCHAIN_HAS_RUN TRUE CACHE BOOL "Has the CMake toolchain run already?" ${FORCE_CACHE})
+
 # By default, search both the specified iOS SDK and the remainder of the host filesystem.
 if(NOT CMAKE_FIND_ROOT_PATH_MODE_PROGRAM)
   set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM BOTH CACHE STRING "" ${FORCE_CACHE})