diff --git a/Modules/Compiler/GNU.cmake b/Modules/Compiler/GNU.cmake index 8d6f5dfb8..bdcaf9d62 100644 --- a/Modules/Compiler/GNU.cmake +++ b/Modules/Compiler/GNU.cmake @@ -24,6 +24,15 @@ macro(__compiler_gnu lang) set(CMAKE_SHARED_LIBRARY_${lang}_FLAGS "-fPIC") set(CMAKE_SHARED_LIBRARY_CREATE_${lang}_FLAGS "-shared") + # Older versions of gcc (< 4.5) contain a bug causing them to report a missing + # header file as a warning if depfiles are enabled, causing check_header_file + # tests to always succeed. Work around this by disabling dependency tracking + # in try_compile mode. + GET_PROPERTY(_IN_TC GLOBAL PROPERTY IN_TRY_COMPILE) + if(NOT _IN_TC OR CMAKE_FORCE_DEPFILES) + set(CMAKE_DEPFILE_FLAGS_${lang} "-MMD -MF ") + endif() + # Initial configuration flags. set(CMAKE_${lang}_FLAGS_INIT "") set(CMAKE_${lang}_FLAGS_DEBUG_INIT "-g") diff --git a/Tests/BuildDepends/CMakeLists.txt b/Tests/BuildDepends/CMakeLists.txt index 31392b5e4..aa32d67a0 100644 --- a/Tests/BuildDepends/CMakeLists.txt +++ b/Tests/BuildDepends/CMakeLists.txt @@ -40,6 +40,8 @@ if("${CMAKE_GENERATOR}" MATCHES "Make") endif() list(APPEND _cmake_options "-DTEST_LINK_DEPENDS=${TEST_LINK_DEPENDS}") +list(APPEND _cmake_options "-DCMAKE_FORCE_DEPFILES=1") + file(MAKE_DIRECTORY ${BuildDepends_BINARY_DIR}/Project) message("Creating Project/foo.cxx") write_file(${BuildDepends_BINARY_DIR}/Project/foo.cxx