• Sebastien Carlier's avatar
    Switch from archive libraries to partial linking · 6d8962e8
    Sebastien Carlier authored
    Before this commit, weak symbols were not overridden by non-weak symbols
    found in archive libraries when linking with recent versions of
    binutils.  As stated in the System V ABI, "the link editor does not
    extract archive members to resolve undefined weak symbols".
    
    This commit changes all Makefiles to use partial linking (ld -r) instead
    of creating library archives, which forces all symbols to participate in
    linking, allowing non-weak symbols to override weak symbols as intended.
    This approach is also used by Linux, from which the gmake function
    cmd_link_o_target (defined in config.mk and used in all Makefiles) is
    inspired.
    
    The name of each former library archive is preserved except for
    extensions which change from ".a" to ".o".  This commit updates
    references accordingly where needed, in particular in some linker
    scripts.
    
    This commit reveals board configurations that exclude some features but
    include source files that depend these disabled features in the build,
    resulting in undefined symbols.  Known such cases include:
    - disabling CMD_NET but not CMD_NFS;
    - enabling CONFIG_OF_LIBFDT but not CONFIG_QE.
    Signed-off-by: 's avatarSebastien Carlier <sebastien.carlier@gmail.com>
    6d8962e8
Makefile 1.39 KB