CMake macro to detect glibc version by filename.

glibc.cmake

# - Check glibc version
# CHECK_GLIBC_VERSION()
# 
# Once done this will define
#
#   GLIBC_VERSION - glibc version
#
MACRO (CHECK_GLIBC_VERSION)
    EXECUTE_PROCESS (
        COMMAND ${CMAKE_C_COMPILER} -print-file-name=libc.so.6
	OUTPUT_VARIABLE GLIBC
	OUTPUT_STRIP_TRAILING_WHITESPACE)

    GET_FILENAME_COMPONENT (GLIBC ${GLIBC} REALPATH)
    GET_FILENAME_COMPONENT (GLIBC_VERSION ${GLIBC} NAME)
    STRING (REPLACE "libc-" "" GLIBC_VERSION ${GLIBC_VERSION})
    STRING (REPLACE ".so" "" GLIBC_VERSION ${GLIBC_VERSION})
    IF (NOT GLIBC_VERSION MATCHES "^[0-9.]+$")
        MESSAGE (FATAL_ERROR "Unknown glibc version: ${GLIBC_VERSION}")
    ENDIF (NOT GLIBC_VERSION MATCHES "^[0-9.]+$")
ENDMACRO (CHECK_GLIBC_VERSION)

Check glibc version if it is composed of 0, ..., 9 and .

This will fail if the base file is libc.so.6 ... which it often is.

This will fail if the base file is libc.so.6 ... which it often is.

What do you mean?

What do you mean?

I mean, that the filename doesn't include the glibc version - and this module assumes that it does and tries to parse the name to get the version.

Any suggestions ?

Well, one thing which often works - not sure whether it always works - is run libc.so.6. Yes, it's typically executable - and prints version information.