csu/Makefile

   1 # Makefile for csu code for GNU C library.
   2
   3 # Copyright (C) 1995 Free Software Foundation, Inc.
   4 # This file is part of the GNU C Library.
   5
   6 # The GNU C Library is free software; you can redistribute it and/or
   7 # modify it under the terms of the GNU Library General Public License
   8 # as published by the Free Software Foundation; either version 2 of
   9 # the License, or (at your option) any later version.
  10
  11 # The GNU C Library is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 # Library General Public License for more details.
  15
  16 # You should have received a copy of the GNU Library General Public
  17 # License along with the GNU C Library; see the file COPYING.LIB.  If
  18 # not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  19 # Cambridge, MA 02139, USA.
  20
  21 # This directory contains the C startup code (that which calls main).  This
  22 # consists of the startfile, built from start.c and installed as crt0.o
  23 # (traditionally) or crt1.o (for ELF); and some initialization code which
  24 # is in the C library itself.  In ELF we also install crti.o and crtn.o,
  25 # special "initializer" and "finalizer" files in used in the link to make
  26 # the .init and .fini sections work right; both these files are built (in
  27 # an arcane manner) from initfini.c.
  28
  29 subdir := csu
  30
  31 csu-dummies = $(filter-out $(start-installed-name),crt1.o Mcrt1.o)
  32 extra-objs = start.o $(start-installed-name) $(csu-dummies)
  33 omit-deps = $(patsubst %.o,%,$(start-installed-name) $(csu-dummies))
  34 install-lib = $(start-installed-name) $(csu-dummies)
  35 distribute = initfini.c
  36
  37 all: # Make this the default target; it will be defined in Rules.
  38
  39 include ../Makeconfig
  40
  41 ifneq ($(elf),yes)
  42 # When not using ELF, there is just one startfile, called crt0.o.
  43 start-installed-name = crt0.o
  44 else
  45 # In the ELF universe, crt0.o is called crt1.o, and there are
  46 # some additional bizarre files.
  47 start-installed-name = crt1.o
  48 install-lib += crti.o crtn.o
  49 extra-objs += crti.o crtn.o
  50 generated += crti.s crtn.s
  51 omit-deps += crti crtn
  52
  53 # Compile initfini.c to assembly code, which contains embedded shell
  54 # commands that prodice crti.s-new and crtn.s-new when run.  We need to
  55 # disable emission of .size directives and debugging information, since
  56 # they will get confused by the splitting of the output we do.
  57 $(objpfx)cr%i.s $(objpfx)cr%n.s: initfini.c
  58         -rm -f $(objpfx)crtcommon.tmp
  59         (echo 'cat > crtcommon.tmp <<\EOF_common'; \
  60          $(CC) $< $(CPPFLAGS) $(CFLAGS) -finhibit-size-directive -g0 -S -o -; \
  61          echo 'EOF_common') | (cd $(@D); $(SHELL))
  62         cat $(objpfx)crtcommon.tmp >> $(objpfx)crti.s-new
  63         cat $(objpfx)crtcommon.tmp >> $(objpfx)crtn.s-new
  64         rm -f $(objpfx)crtcommon.tmp
  65         mv -f $(objpfx)crti.s-new $(objpfx)crti.s
  66         mv -f $(objpfx)crtn.s-new $(objpfx)crtn.s
  67 endif
  68
  69
  70 include ../Rules
  71
  72 # The startfile is installed under different names, so we just call our
  73 # source file `start.c' and copy to the installed name after compiling.
  74 $(objpfx)$(start-installed-name): $(objpfx)start.o
  75         -rm -f $@
  76         ln $< $@
  77
  78 # These extra files are sometimes expected by system standard linking
  79 # procedures, but we have nothing for them to do.  So compile empty files.
  80 $(addprefix $(objpfx),$(filter-out $(start-installed-name),$(csu-dummies))):
  81         cp /dev/null $(@:.o=.c)
  82         $(COMPILE.c) $(@:.o=.c) $(OUTPUT_OPTION)
  83         rm -f $(@:.o=.c)
  84