Merge pull request #1613 from hexane360/cmake-fixes

CMake pre-compiled header and warning fixes

2 files changed, 40 insertions, 5 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fad1af6f3..04e023c09 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -112,14 +112,17 @@ if (APPLE)
 endif ()
 
 if (CMAKE_SYSTEM_NAME STREQUAL "Linux")
-    # Workaround for an old CMake, which does not understand CMAKE_CXX_STANDARD.
-    add_compile_options(-std=c++11 -Wall -Wno-reorder)
     find_package(PkgConfig REQUIRED)
+
+    if (CMAKE_VERSION VERSION_LESS "3.1")
+        # Workaround for an old CMake, which does not understand CMAKE_CXX_STANDARD.
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+    endif()
 endif()
 
 if (CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_GNUXX)
     # Adding -fext-numeric-literals to enable GCC extensions on definitions of quad float literals, which are required by Boost.
-    add_compile_options(-fext-numeric-literals)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fext-numeric-literals" )
 
     if (SLIC3R_SYNTAXONLY)
         set(CMAKE_CXX_ARCHIVE_CREATE "true")
@@ -136,9 +139,15 @@ if (CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_GNUXX)
 endif()
 
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
+    add_compile_options(-Wall)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-reorder" )
+
     # On GCC and Clang, no return from a non-void function is a warning only. Here, we make it an error.
     add_compile_options(-Werror=return-type)
 
+    #removes LOTS of extraneous Eigen warnings
+    add_compile_options(-Wno-ignored-attributes)
+
     if (SLIC3R_ASAN)
         add_compile_options(-fsanitize=address -fno-omit-frame-pointer)
         set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fsanitize=address")
@@ -245,7 +254,7 @@ endif()
 
 # Find eigen3 or use bundled version
 if (NOT SLIC3R_STATIC)
-    find_package(Eigen3)
+    find_package(Eigen3 3)
 endif ()
 if (NOT Eigen3_FOUND)
     set(Eigen3_FOUND 1)
diff --git a/cmake/modules/PrecompiledHeader.cmake b/cmake/modules/PrecompiledHeader.cmake
index 2880da9f2..e46302144 100644
--- a/cmake/modules/PrecompiledHeader.cmake
+++ b/cmake/modules/PrecompiledHeader.cmake
@@ -68,11 +68,37 @@ function(export_all_flags _filename)
   set(_compile_definitions "$<TARGET_PROPERTY:${_target},COMPILE_DEFINITIONS>")
   set(_compile_flags "$<TARGET_PROPERTY:${_target},COMPILE_FLAGS>")
   set(_compile_options "$<TARGET_PROPERTY:${_target},COMPILE_OPTIONS>")
+
+  #handle config-specific cxx flags
+  string(TOUPPER ${CMAKE_BUILD_TYPE} _config)
+  set(_build_cxx_flags ${CMAKE_CXX_FLAGS_${_config}})
+
+  #handle fpie option
+  get_target_property(_fpie ${_target} POSITION_INDEPENDENT_CODE)
+  if (_fpie AND CMAKE_POSITION_INDEPENDENT_CODE)
+    list(APPEND _compile_options ${CMAKE_CXX_COMPILE_OPTIONS_PIC})
+  endif()
+
+  #handle compiler standard (GCC only)
+  if(CMAKE_COMPILER_IS_GNUCXX)
+    get_target_property(_cxx_standard ${_target} CXX_STANDARD)
+    if ((NOT "${_cxx_standard}" STREQUAL NOTFOUND) AND (NOT "${_cxx_standard}" STREQUAL ""))
+      get_target_property(_cxx_extensions ${_target} CXX_EXTENSIONS)
+      get_property(_exists TARGET ${_target} PROPERTY CXX_EXTENSIONS SET)
+      if (NOT _exists OR ${_cxx_extensions})
+        list(APPEND _compile_options "-std=gnu++${_cxx_standard}")
+      else()
+        list(APPEND _compile_options "-std=c++${_cxx_standard}")
+      endif()
+    endif()
+  endif()
+
   set(_include_directories "$<$<BOOL:${_include_directories}>:-I$<JOIN:${_include_directories},\n-I>\n>")
   set(_compile_definitions "$<$<BOOL:${_compile_definitions}>:-D$<JOIN:${_compile_definitions},\n-D>\n>")
   set(_compile_flags "$<$<BOOL:${_compile_flags}>:$<JOIN:${_compile_flags},\n>\n>")
   set(_compile_options "$<$<BOOL:${_compile_options}>:$<JOIN:${_compile_options},\n>\n>")
-  file(GENERATE OUTPUT "${_filename}" CONTENT "${_compile_definitions}${_include_directories}${_compile_flags}${_compile_options}\n")
+  set(_cxx_flags "$<$<BOOL:${CMAKE_CXX_FLAGS}>:${CMAKE_CXX_FLAGS}\n>$<$<BOOL:${_build_cxx_flags}>:${_build_cxx_flags}\n>")
+  file(GENERATE OUTPUT "${_filename}" CONTENT "${_compile_definitions}${_include_directories}${_compile_flags}${_compile_options}${_cxx_flags}\n")
 endfunction()
 
 function(add_precompiled_header _target _input)