diff --git a/containers/CMakeLists.txt b/containers/CMakeLists.txt
index a29a885..5570038 100644
--- a/containers/CMakeLists.txt
+++ b/containers/CMakeLists.txt
@@ -13,7 +13,7 @@ add_definitions(-DDL_PATH_PREFIX="${VMCS_PLUGIN_DIR}/")
 
 SET( GCC_COMPILER_FLAGS -Wall -g -O2 -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -Wcast-qual -Wwrite-strings -Wundef )
 SET( GCC_COMPILER_FLAGS ${GCC_COMPILER_FLAGS} -Wextra )#-Wno-missing-field-initializers )
-SET( GCC_COMPILER_FLAGS ${GCC_COMPILER_FLAGS} -std=c99 -D_POSIX_C_SOURCE=199309L )
+SET( GCC_COMPILER_FLAGS ${GCC_COMPILER_FLAGS} -std=c99 -D_POSIX_C_SOURCE=200112L )
 SET( GCC_COMPILER_FLAGS ${GCC_COMPILER_FLAGS} -Wno-missing-field-initializers )
 SET( GCC_COMPILER_FLAGS ${GCC_COMPILER_FLAGS} -Wno-unused-value )