Fix gcc optimization level for debug builds
This fixes a minor "bug" I happened to notice. For gcc, we were setting
the optimization level to -O2 for all builds instead of just for
CMAKE_BUILD_TYPE=release. Debug builds should be -Og or -O0, otherwise
a debugger is not useful (source code no longer matches up 1-to-1 with
executable), defeating the purpose of CMAKE_BUILD_TYPE=debug. The comment
makes clear that the intention was to lower the optimization in
release builds from -O3 to -O2, but the way this was done also raised
the optimization of debug builds (as well as all other build types) from
-Og to -O2
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7231565..1d9199e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -64,7 +64,7 @@
SET(CMAKE_CXX_FLAGS_RELEASE "-O1 -DNDEBUG"
CACHE STRING
"Flags used by the CXX compiler during RELEASE builds." FORCE)
- SET(CMAKE_CXX_FLAGS_DEBUG "-O0 -g"
+ SET(CMAKE_CXX_FLAGS_DEBUG "-Og -g"
CACHE STRING
"Flags used by the CXX compiler during DEBUG builds." FORCE)
SET(CMAKE_CXX_FLAGS_MINSIZEREL "-Os -DNDEBUG"
@@ -129,7 +129,9 @@
if((CMAKE_C_COMPILER_VERSION VERSION_EQUAL 5.0) OR (CMAKE_C_COMPILER_VERSION VERSION_GREATER 5.0))
# Versions 5+ fail with the "Release" build type i.e. when optimization
# level is -O3 or greater.
- add_compile_options("-O2")
+ # For CXX11, we've already limited it to -O1 for similar reasons (causes crash)
+ SET(CMAKE_C_FLAGS_RELEASE "-O2 -DNDEBUG" CACHE STRING
+ "Flags used by the C compiler during RELEASE builds." FORCE)
endif()
# See comments below for C++:
@@ -175,13 +177,14 @@
set(CMAKE_C_FLAGS "-std=gnu99 ${CMAKE_C_FLAGS}"
CACHE STRING
"Flags used by the compiler during all build types." FORCE)
+ if((CMAKE_CXX_COMPILER_VERSION VERSION_EQUAL 5.0) OR (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 5.0))
+ # Versions 5+ fail with the "Release" build type i.e. when optimization
+ # level is -O3 or greater.
+ SET(CMAKE_CXX_FLAGS_RELEASE "-O2 -DNDEBUG" CACHE STRING
+ "Flags used by the CXX compiler during RELEASE builds." FORCE)
+ endif()
endif(CXX11)
- if((CMAKE_CXX_COMPILER_VERSION VERSION_EQUAL 5.0) OR (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 5.0))
- # Versions 5+ fail with the "Release" build type i.e. when optimization
- # level is -O3 or greater.
- add_compile_options("-O2")
- endif()
# We want to include some header files as system header files in order to
# disable warnings. However, on Mac OS X, a CMake variable is not set
# correctly on Mac OS X. http://www.cmake.org/Bug/view.php?id=10837
