Using cmake_cxx_flags instead of add_definitions

autoload/youcompleteme.vim

@@ -30,6 +30,7 @@ function! youcompleteme#Enable()
   augroup youcompleteme
     autocmd!
     autocmd CursorMovedI * call s:OnMovedI()
+    " BufWinEnter/Leave?
     autocmd BufRead,BufEnter * call s:OnBufferVisit()
     autocmd CursorHold,CursorHoldI * call s:OnCursorHold()
   augroup END

cpp/BoostParts/CMakeLists.txt

@@ -77,7 +77,7 @@ add_library( BoostParts ${SOURCES} )
 if( CMAKE_COMPILER_IS_GNUCXX OR COMPILER_IS_CLANG )
   # No warnings. We just use Boost as is so warnings coming from it are just
   # noise.
-  add_definitions( -w )
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -w")
 endif()
 
 #############################################################################

cpp/CMakeLists.txt

@@ -21,19 +21,20 @@ project( YouCompleteMe )
 # This is needed so that on macs, the library is built in both 32 bit and 64 bit
 # versions. Without this python might refuse to load the module, depending on
 # how python was built.
-# On Mac, boost needs to be compiled universal as well. For brew, that's
+# On Mac, boost needs to be compiled universal as well, if used instead of the
+# included BoostParts lib. For brew, that's
 # "brew install boost --universal"
 set( CMAKE_OSX_ARCHITECTURES "i386;x86_64" )
 
-# Force release build, speed is of the essence
-if ( NOT CMAKE_BUILD_TYPE )
-  set( CMAKE_BUILD_TYPE RELEASE )
-endif()
-
 if ( CMAKE_CXX_COMPILER_ID STREQUAL "Clang" )
   set( COMPILER_IS_CLANG true )
 endif()
 
+# Force release build by default, speed is of the essence
+if ( NOT CMAKE_BUILD_TYPE )
+  set( CMAKE_BUILD_TYPE Release )
+endif()
+
 # Determining the presence of C++11 support in the compiler
 set( CPP11_AVAILABLE false )
 if ( CMAKE_COMPILER_IS_GNUCXX )
@@ -46,16 +47,23 @@ elseif( COMPILER_IS_CLANG )
   set( CPP11_AVAILABLE true )
 endif()
 
+# When used with Clang, adding the -std=c++0x flag to CMAKE_CXX_FLAGS will cause
+# the compiler to output a warning during linking:
+#  clang: warning: argument unused during compilation: '-std=c++0x'
+# This is caused by cmake passing this flag to the linking stage which it
+# shouldn't do. It's ignored so it does no harm, but the warning is annoying and
+# there's no way around the problem (the flag is correctly used during the
+# compilation stage). We could use add_definitions(-std=c++0x), but this will
+# break the llvm build since the flag will then be used when compiling C code
+# too. Sadly there's no way around the warning.
 if ( CPP11_AVAILABLE )
   message( "Your C++ compiler supports C++11, compiling in that mode." )
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")
+  set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x" )
 else()
   message(
     "Your C++ compiler does NOT support C++11, compiling in C++03 mode." )
 endif()
 
-#-Wc++11-extensions
-
 add_subdirectory( llvm )
 add_subdirectory( BoostParts )
 add_subdirectory( ycm )

cpp/ycm/CMakeLists.txt

@@ -80,7 +80,14 @@ set_target_properties( ${PROJECT_NAME} PROPERTIES
 
 if( CMAKE_COMPILER_IS_GNUCXX OR COMPILER_IS_CLANG )
   # We want all warnings, and warnings should be treated as errors
-  add_definitions( -Wall -Wextra -Werror )
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Werror")
+endif()
+
+#############################################################################
+
+# We want warnings if we accidentally use C++11 features
+if ( COMPILER_IS_CLANG )
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wc++11-extensions")
 endif()
 
 #############################################################################

cpp/ycm/tests/CMakeLists.txt

@@ -20,7 +20,8 @@ cmake_minimum_required( VERSION 2.8 )
 
 # The gtest library triggers these silly warnings, so we turn them off
 if ( COMPILER_IS_CLANG )
-  add_definitions( -Wno-long-long -Wno-variadic-macros )
+  set( CMAKE_CXX_FLAGS
+    "${CMAKE_CXX_FLAGS} -Wno-long-long -Wno-variadic-macros" )
 endif()
 
 add_subdirectory( gmock )