-exec_program("echo `${CMAKE_C_COMPILER} --version | grep -E [0-9].[0-9].[0-9]$`" OUTPUT_VARIABLE "COMPILER_C_VERSION")
-exec_program("echo `${CMAKE_CXX_COMPILER} --version | grep -E [0-9].[0-9].[0-9]$`" OUTPUT_VARIABLE "COMPILER_CXX_VERSION")
+exec_program("${CMAKE_C_COMPILER} --version" OUTPUT_VARIABLE "COMPILER_C_VERSION")
+exec_program("${CMAKE_CXX_COMPILER} --version" OUTPUT_VARIABLE "COMPILER_CXX_VERSION")
+
+string(REGEX MATCH "[0-9].[0-9].[0-9]" COMPILER_C_VERSION "${COMPILER_C_VERSION}")
+string(REGEX MATCH "[0-9].[0-9].[0-9]" COMPILER_CXX_VERSION "${COMPILER_CXX_VERSION}")