change in how cmake works with CMAKE_C_STANDARD_LIBRARIES / CMAKE_CXX_STANDARD_LIBRARIES.

if not defined (first run) these are now set blank but can be defined later.

the problem is that scons & cmake builds would link against different libraries since cmake added its own defaults.
now, by default, scons & cmake have the same libraries.

This fixes an obscure crash in MinGW where cmakes default linking with -ladvapi32 would crash on string formatting which used float precision as an argument, eg:
  printf("%.*f", 3, value);
...without giving a useful backtrace or pointing to the line of code doing the string formatting.

1 files changed, 25 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ef8b8efc772..b0da2360b84 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -50,8 +50,33 @@ set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/build_files/cmake/Modules/")
 # quiet output for Makefiles, 'make -s' helps too
 # set_property(GLOBAL PROPERTY RULE_MESSAGES OFF)
 
+# ignore system set flag, use our own
+# must be before project(...)
+# if the user wants to add their own its ok after first run.
+if(DEFINED CMAKE_C_STANDARD_LIBRARIES)
+	set(_reset_standard_libraries OFF)
+else()
+	set(_reset_standard_libraries ON)
+endif()
+
+
 project(Blender)
 
+
+if (_reset_standard_libraries)
+	message("Reset Libs")
+	# Must come after project(...)
+	#
+	# MINGW workaround for -ladvapi32 being included which surprisingly causes
+	# string formatting of floats, eg: printf("%.*f", 3, value). to crash blender
+	# with a meaningless stack trace. by overriding this flag we ensure we only
+	# have libs we define and that cmake & scons builds match.
+	set(CMAKE_C_STANDARD_LIBRARIES "" CACHE STRING "" FORCE)
+	set(CMAKE_CXX_STANDARD_LIBRARIES "" CACHE STRING "" FORCE)
+endif()
+unset(_reset_standard_libraries)
+
+
 enable_testing()
 
 #-----------------------------------------------------------------------------