2 # Copyright (C) 1999-2013 Free Software Foundation, Inc.
4 # This file is free software; the Free Software Foundation
5 # gives unlimited permission to copy and/or distribute it,
6 # with or without modifications, as long as this notice is preserved.
9 # There are a few dirty hacks below to avoid letting 'AC_PROG_CC' be
10 # written in clear, in which case automake, when reading aclocal.m4,
11 # will think it sees a *use*, and therefore will trigger all it's
12 # C support machinery. Also note that it means that autoscan, seeing
13 # CC etc. in the Makefile, will ask for an AC_PROG_CC use...
16 # _AM_DEPENDENCIES(NAME)
17 # ----------------------
18 # See how the compiler implements dependency checking.
19 # NAME is "CC", "CXX", "OBJC", "OBJCXX", "UPC", or "GJC".
20 # We try a few techniques and use that to set a single cache variable.
22 # We don't AC_REQUIRE the corresponding AC_PROG_CC since the latter was
23 # modified to invoke _AM_DEPENDENCIES(CC); we would have a circular
24 # dependency, and given that the user is not expected to run this macro,
25 # just rely on AC_PROG_CC.
26 AC_DEFUN([_AM_DEPENDENCIES],
27 [AC_REQUIRE([AM_SET_DEPDIR])dnl
28 AC_REQUIRE([AM_OUTPUT_DEPENDENCY_COMMANDS])dnl
29 AC_REQUIRE([AM_MAKE_INCLUDE])dnl
30 AC_REQUIRE([AM_DEP_TRACK])dnl
32 m4_if([$1], [CC], [depcc="$CC" am_compiler_list=],
33 [$1], [CXX], [depcc="$CXX" am_compiler_list=],
34 [$1], [OBJC], [depcc="$OBJC" am_compiler_list='gcc3 gcc'],
35 [$1], [OBJCXX], [depcc="$OBJCXX" am_compiler_list='gcc3 gcc'],
36 [$1], [UPC], [depcc="$UPC" am_compiler_list=],
37 [$1], [GCJ], [depcc="$GCJ" am_compiler_list='gcc3 gcc'],
38 [depcc="$$1" am_compiler_list=])
40 AC_CACHE_CHECK([dependency style of $depcc],
41 [am_cv_$1_dependencies_compiler_type],
42 [if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
43 # We make a subdir and do the tests there. Otherwise we can end up
44 # making bogus files that we don't know about and never remove. For
45 # instance it was reported that on HP-UX the gcc test will end up
46 # making a dummy file named 'D' -- because '-MD' means "put the output
50 # Copy depcomp to subdir because otherwise we won't find it if we're
51 # using a relative directory.
52 cp "$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`
68 [case " $depcc " in #(
69 *\ -arch\ *\ -arch\ *) am__universal=true ;;
72 [case " $depcc " in #(
73 *\ -arch\ *\ -arch\ *) am__universal=true ;;
76 for depmode in $am_compiler_list; do
77 # Setup a source with many dependencies, because some compilers
78 # like to wrap large dependency lists on column 80 (with \), and
79 # we should not choose a depcomp mode which is confused by this.
81 # We need to recreate these files for each test, as the compiler may
82 # overwrite some of them when testing with obscure command lines.
83 # This happens at least with the AIX C compiler.
85 for i in 1 2 3 4 5 6; do
86 echo '#include "conftst'$i'.h"' >> sub/conftest.c
87 # Using ": > sub/conftst$i.h" creates only sub/conftst1.h with
89 echo '/* dummy */' > sub/conftst$i.h
91 echo "${am__include} ${am__quote}sub/conftest.Po${am__quote}" > confmf
93 # We check with '-c' and '-o' for the sake of the "dashmstdout"
94 # mode. It turns out that the SunPro C++ compiler does not properly
95 # handle '-M -o', and we need to detect this. Also, some Intel
96 # versions had trouble with output in subdirs.
97 am__obj=sub/conftest.${OBJEXT-o}
98 am__minus_obj="-o $am__obj"
101 # This depmode causes a compiler race in universal mode.
102 test "$am__universal" = false || continue
105 # After this tag, mechanisms are not by side-effect, so they'll
106 # only be used when explicitly requested.
107 if test "x$enable_dependency_tracking" = xyes; then
113 msvc7 | msvc7msys | msvisualcpp | msvcmsys)
114 # This compiler won't grok '-c -o', but also, the minuso test has
115 # not run yet. These depmodes are late enough in the game, and
116 # so weak that their functioning should not be impacted.
117 am__obj=conftest.${OBJEXT-o}
122 if depmode=$depmode \
123 source=sub/conftest.c object=$am__obj \
124 depfile=sub/conftest.Po tmpdepfile=sub/conftest.TPo \
125 $SHELL ./depcomp $depcc -c $am__minus_obj sub/conftest.c \
126 >/dev/null 2>conftest.err &&
127 grep sub/conftst1.h sub/conftest.Po > /dev/null 2>&1 &&
128 grep sub/conftst6.h sub/conftest.Po > /dev/null 2>&1 &&
129 grep $am__obj sub/conftest.Po > /dev/null 2>&1 &&
130 ${MAKE-make} -s -f confmf > /dev/null 2>&1; then
131 # icc doesn't choke on unknown options, it will just issue warnings
132 # or remarks (even with -Werror). So we grep stderr for any message
133 # that says an option was ignored or not supported.
134 # When given -MP, icc 7.0 and 7.1 complain thusly:
135 # icc: Command line warning: ignoring option '-M'; no argument required
136 # The diagnosis changed in icc 8.0:
137 # icc: Command line remark: option '-MP' not supported
138 if (grep 'ignoring option' conftest.err ||
139 grep 'not supported' conftest.err) >/dev/null 2>&1; then :; else
140 am_cv_$1_dependencies_compiler_type=$depmode
149 am_cv_$1_dependencies_compiler_type=none
152 AC_SUBST([$1DEPMODE], [depmode=$am_cv_$1_dependencies_compiler_type])
153 AM_CONDITIONAL([am__fastdep$1], [
154 test "x$enable_dependency_tracking" != xno \
155 && test "$am_cv_$1_dependencies_compiler_type" = gcc3])
161 # Choose a directory name for dependency files.
162 # This macro is AC_REQUIREd in _AM_DEPENDENCIES.
163 AC_DEFUN([AM_SET_DEPDIR],
164 [AC_REQUIRE([AM_SET_LEADING_DOT])dnl
165 AC_SUBST([DEPDIR], ["${am__leading_dot}deps"])dnl
171 AC_DEFUN([AM_DEP_TRACK],
172 [AC_ARG_ENABLE([dependency-tracking], [dnl
174 [--enable-dependency-tracking],
175 [do not reject slow dependency extractors])
177 [--disable-dependency-tracking],
178 [speeds up one-time build])])
179 if test "x$enable_dependency_tracking" != xno; then
180 am_depcomp="$ac_aux_dir/depcomp"
184 AM_CONDITIONAL([AMDEP], [test "x$enable_dependency_tracking" != xno])
185 AC_SUBST([AMDEPBACKSLASH])dnl
186 _AM_SUBST_NOTMAKE([AMDEPBACKSLASH])dnl
187 AC_SUBST([am__nodep])dnl
188 _AM_SUBST_NOTMAKE([am__nodep])dnl