2 # Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
3 # Free Software Foundation, Inc.
5 # This file is free software; the Free Software Foundation
6 # gives unlimited permission to copy and/or distribute it,
7 # with or without modifications, as long as this notice is preserved.
11 # There are a few dirty hacks below to avoid letting `AC_PROG_CC' be
12 # written in clear, in which case automake, when reading aclocal.m4,
13 # will think it sees a *use*, and therefore will trigger all it's
14 # C support machinery. Also note that it means that autoscan, seeing
15 # CC etc. in the Makefile, will ask for an AC_PROG_CC use...
18 # _AM_DEPENDENCIES(NAME)
19 # ----------------------
20 # See how the compiler implements dependency checking.
21 # NAME is "CC", "CXX", "GCJ", or "OBJC".
22 # We try a few techniques and use that to set a single cache variable.
24 # We don't AC_REQUIRE the corresponding AC_PROG_CC since the latter was
25 # modified to invoke _AM_DEPENDENCIES(CC); we would have a circular
26 # dependency, and given that the user is not expected to run this macro,
27 # just rely on AC_PROG_CC.
28 AC_DEFUN([_AM_DEPENDENCIES],
29 [AC_REQUIRE([AM_SET_DEPDIR])dnl
30 AC_REQUIRE([AM_OUTPUT_DEPENDENCY_COMMANDS])dnl
31 AC_REQUIRE([AM_MAKE_INCLUDE])dnl
32 AC_REQUIRE([AM_DEP_TRACK])dnl
34 ifelse([$1], CC, [depcc="$CC" am_compiler_list=],
35 [$1], CXX, [depcc="$CXX" am_compiler_list=],
36 [$1], OBJC, [depcc="$OBJC" am_compiler_list='gcc3 gcc'],
37 [$1], UPC, [depcc="$UPC" am_compiler_list=],
38 [$1], GCJ, [depcc="$GCJ" am_compiler_list='gcc3 gcc'],
39 [depcc="$$1" am_compiler_list=])
41 AC_CACHE_CHECK([dependency style of $depcc],
42 [am_cv_$1_dependencies_compiler_type],
43 [if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
44 # We make a subdir and do the tests there. Otherwise we can end up
45 # making bogus files that we don't know about and never remove. For
46 # instance it was reported that on HP-UX the gcc test will end up
47 # making a dummy file named `D' -- because `-MD' means `put the output
50 # Copy depcomp to subdir because otherwise we won't find it if we're
51 # using a relative directory.
52 cp "$am_depcomp" conftest.dir
54 # We will build objects and dependencies in a subdirectory because
55 # it helps to detect inapplicable dependency modes. For instance
56 # both Tru64's cc and ICC support -MD to output dependencies as a
57 # side effect of compilation, but ICC will put the dependencies in
58 # the current directory while Tru64 will put them in the object
62 am_cv_$1_dependencies_compiler_type=none
63 if test "$am_compiler_list" = ""; then
64 am_compiler_list=`sed -n ['s/^#*\([a-zA-Z0-9]*\))$/\1/p'] < ./depcomp`
66 for depmode in $am_compiler_list; do
67 # Setup a source with many dependencies, because some compilers
68 # like to wrap large dependency lists on column 80 (with \), and
69 # we should not choose a depcomp mode which is confused by this.
71 # We need to recreate these files for each test, as the compiler may
72 # overwrite some of them when testing with obscure command lines.
73 # This happens at least with the AIX C compiler.
75 for i in 1 2 3 4 5 6; do
76 echo '#include "conftst'$i'.h"' >> sub/conftest.c
77 # Using `: > sub/conftst$i.h' creates only sub/conftst1.h with
78 # Solaris 8's {/usr,}/bin/sh.
81 echo "${am__include} ${am__quote}sub/conftest.Po${am__quote}" > confmf
85 # after this tag, mechanisms are not by side-effect, so they'll
86 # only be used when explicitly requested
87 if test "x$enable_dependency_tracking" = xyes; then
95 # We check with `-c' and `-o' for the sake of the "dashmstdout"
96 # mode. It turns out that the SunPro C++ compiler does not properly
97 # handle `-M -o', and we need to detect this.
99 source=sub/conftest.c object=sub/conftest.${OBJEXT-o} \
100 depfile=sub/conftest.Po tmpdepfile=sub/conftest.TPo \
101 $SHELL ./depcomp $depcc -c -o sub/conftest.${OBJEXT-o} sub/conftest.c \
102 >/dev/null 2>conftest.err &&
103 grep sub/conftst1.h sub/conftest.Po > /dev/null 2>&1 &&
104 grep sub/conftst6.h sub/conftest.Po > /dev/null 2>&1 &&
105 grep sub/conftest.${OBJEXT-o} sub/conftest.Po > /dev/null 2>&1 &&
106 ${MAKE-make} -s -f confmf > /dev/null 2>&1; then
107 # icc doesn't choke on unknown options, it will just issue warnings
108 # or remarks (even with -Werror). So we grep stderr for any message
109 # that says an option was ignored or not supported.
110 # When given -MP, icc 7.0 and 7.1 complain thusly:
111 # icc: Command line warning: ignoring option '-M'; no argument required
112 # The diagnosis changed in icc 8.0:
113 # icc: Command line remark: option '-MP' not supported
114 if (grep 'ignoring option' conftest.err ||
115 grep 'not supported' conftest.err) >/dev/null 2>&1; then :; else
116 am_cv_$1_dependencies_compiler_type=$depmode
125 am_cv_$1_dependencies_compiler_type=none
128 AC_SUBST([$1DEPMODE], [depmode=$am_cv_$1_dependencies_compiler_type])
129 AM_CONDITIONAL([am__fastdep$1], [
130 test "x$enable_dependency_tracking" != xno \
131 && test "$am_cv_$1_dependencies_compiler_type" = gcc3])
137 # Choose a directory name for dependency files.
138 # This macro is AC_REQUIREd in _AM_DEPENDENCIES
139 AC_DEFUN([AM_SET_DEPDIR],
140 [AC_REQUIRE([AM_SET_LEADING_DOT])dnl
141 AC_SUBST([DEPDIR], ["${am__leading_dot}deps"])dnl
147 AC_DEFUN([AM_DEP_TRACK],
148 [AC_ARG_ENABLE(dependency-tracking,
149 [ --disable-dependency-tracking speeds up one-time build
150 --enable-dependency-tracking do not reject slow dependency extractors])
151 if test "x$enable_dependency_tracking" != xno; then
152 am_depcomp="$ac_aux_dir/depcomp"
155 AM_CONDITIONAL([AMDEP], [test "x$enable_dependency_tracking" != xno])
156 AC_SUBST([AMDEPBACKSLASH])dnl
157 _AM_SUBST_NOTMAKE([AMDEPBACKSLASH])dnl