lib: mbedtls: force compiler c99 mode
@@ -154,6 +154,8 @@ string(REGEX MATCH "Clang" CMAKE_COMPILER_IS_CLANG "${CMAKE_C_COMPILER_ID}")
include(CheckCCompilerFlag)
+set(CMAKE_C_FLAGS "${CMAKE_C_CFLAGS} -std=c99")
+
if(CMAKE_COMPILER_IS_GNU)
# some warnings we want are not available with old GCC versions
# note: starting with CMake 2.8 we could use CMAKE_C_COMPILER_VERSION
