• Masahiro Yamada's avatar
    Makefile: move some variable definitions to the top Makefile · f6322eb7
    Masahiro Yamada authored
    This commit moves some variable definitions from config.mk
    to the top Makefile:
    
      - HOSTCC, HOSTCFLAGS, HOSTLDFLAGS
      - AS, LD, CC, CPP, etc.
      - SHELL (renamed to CONFIG_SHELL)
    
    I'd like to slim down config.mk file
    because it is included from all recursive make.
    It is redundant to re-define the variables
    every time descending into sub directories.
    We should rather define them at the top Makefile
    and export them.
    
    U-Boot makefiles has been used "SHELL" variable to store shell
    chosen for the user, whereas Linux Kernel uses "CONFIG_SHELL".
    
    We should never use "SHELL" variable because it is
    a special variable for GNU Make.
    Changing SHELL may cause unpredictable side effects
    whose root cause is usually difficult to find.
    We should use a generic variable name "CONFIG_SHELL".
    
    We should not use the syntax as follows either:
    
        rm -f $(obj)tools/env/{fw_printenv,fw_setenv}
    
    This depends on "bash" although GNU Make generally
    invokes "sh" to run the each rule.
    Signed-off-by: default avatarMasahiro Yamada <yamada.m@jp.panasonic.com>
    f6322eb7
config.mk 6.95 KB