The following topics describe the changes that affect migration and compatibility between RVCT v3.1 and RVCT v4.0:
Default --gnu_version changed from 303000 (GCC 3.3) to 402000 (GCC 4.2)
General changes between RVCT v3.1 and RVCT v4.0
Changes to symbol visibility between RVCT v3.1 and RVCT v4.0
Compiler changes between RVCT v3.1 and RVCT v4.0
Linker changes between RVCT v3.1 and RVCT v4.0
Assembler changes between RVCT v3.1 and RVCT v4.0
fromelf changes between RVCT v3.1 and RVCT v4.0
C and C++ library changes between RVCT v3.1 and RVCT v4.0.