From: Modestas Vainius <modax@debian.org>
Subject: Support CPPFLAGS environment variable
Bug: http://www.cmake.org/Bug/view.php?id=12928
Bug-Debian: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=653916
Forwarded: no
Last-Update: 2012-02-18

For now, append CPPFLAGS to CFLAGS and CXXFLAGS. In the perfect world, whenever
C/C++ preprocessor is invoked, CPPFLAGS should be passed to it.

--- a/Modules/CMakeCInformation.cmake
+++ b/Modules/CMakeCInformation.cmake
@@ -102,7 +102,7 @@ IF(NOT CMAKE_MODULE_EXISTS)
   SET(CMAKE_SHARED_MODULE_CREATE_C_FLAGS ${CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS})
 ENDIF(NOT CMAKE_MODULE_EXISTS)
 
-SET(CMAKE_C_FLAGS_INIT "$ENV{CFLAGS} ${CMAKE_C_FLAGS_INIT}")
+SET(CMAKE_C_FLAGS_INIT "$ENV{CFLAGS} $ENV{CPPFLAGS} ${CMAKE_C_FLAGS_INIT}")
 # avoid just having a space as the initial value for the cache 
 IF(CMAKE_C_FLAGS_INIT STREQUAL " ")
   SET(CMAKE_C_FLAGS_INIT)
--- a/Modules/CMakeCXXInformation.cmake
+++ b/Modules/CMakeCXXInformation.cmake
@@ -183,7 +183,7 @@ ENDFOREACH(type)
 # on the initial values computed in the platform/*.cmake files
 # use _INIT variables so that this only happens the first time
 # and you can set these flags in the cmake cache
-SET(CMAKE_CXX_FLAGS_INIT "$ENV{CXXFLAGS} ${CMAKE_CXX_FLAGS_INIT}")
+SET(CMAKE_CXX_FLAGS_INIT "$ENV{CXXFLAGS} $ENV{CPPFLAGS} ${CMAKE_CXX_FLAGS_INIT}")
 # avoid just having a space as the initial value for the cache 
 IF(CMAKE_CXX_FLAGS_INIT STREQUAL " ")
   SET(CMAKE_CXX_FLAGS_INIT)