dnl See how the compiler implements dependency checking.
dnl Usage:
dnl AM_DEPENDENCIES(NAME)
dnl NAME is "CC", "CXX" or "OBJC".

dnl We try a few techniques and use that to set a single cache variable.

AC_DEFUN(AM_DEPENDENCIES,[
AC_REQUIRE([AM_SET_DEPDIR])
AC_REQUIRE([AM_OUTPUT_DEPENDENCY_COMMANDS])
ifelse([$1],CC,[
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_PROG_CPP])
depcc="$CC"
depcpp="$CPP"],[$1],CXX,[
AC_REQUIRE([AC_PROG_CXX])
AC_REQUIRE([AC_PROG_CXXCPP])
depcc="$CXX"
depcpp="$CXXCPP"],[$1],OBJC,[
am_cv_OBJC_dependencies_compiler_type=gcc],[
AC_REQUIRE([AC_PROG_][$1])
depcc="$[$1]"
depcpp=""])
AC_MSG_CHECKING([dependency style of $depcc])
AC_CACHE_VAL(am_cv_[$1]_dependencies_compiler_type,[
if test -z "$AMDEP"; then
  echo '#include "conftest.h"' > conftest.c
  echo 'int i;' > conftest.h

  am_cv_[$1]_dependencies_compiler_type=none
  for depmode in `sed -n 's/^#*\([a-zA-Z0-9]*\))$/\1/p' < "$am_depcomp"`; do
    case "$depmode" in
    nosideeffect)
      # after this tag, mechanisms are not by side-effect, so they'll
      # only be used when explicitly requested
      if test "x$enable_dependency_tracking" = xyes; then
	continue
      else
	break
      fi
      ;;
    none) break ;;
    esac
    if depmode="$depmode" \
       source=conftest.c object=conftest.o \
       depfile=conftest.Po tmpdepfile=conftest.TPo \
       $SHELL $am_depcomp $depcc -c conftest.c 2>/dev/null &&
       grep conftest.h conftest.Po > /dev/null 2>&1; then
      am_cv_[$1]_dependencies_compiler_type="$depmode"
      break
    fi
  done

  rm -f conftest.*
else
  am_cv_[$1]_dependencies_compiler_type=none
fi
])
AC_MSG_RESULT($am_cv_[$1]_dependencies_compiler_type)
[$1]DEPMODE="depmode=$am_cv_[$1]_dependencies_compiler_type"
AC_SUBST([$1]DEPMODE)
])

dnl Choose a directory name for dependency files.
dnl This macro is AC_REQUIREd in AM_DEPENDENCIES

AC_DEFUN(AM_SET_DEPDIR,[
if test -d .deps || mkdir .deps 2> /dev/null || test -d .deps; then
  DEPDIR=.deps
else
  DEPDIR=_deps
fi
AC_SUBST(DEPDIR)
])

AC_DEFUN(AM_DEP_TRACK,[
AC_ARG_ENABLE(dependency-tracking,
[  --disable-dependency-tracking Speeds up one-time builds
  --enable-dependency-tracking  Do not reject slow dependency extractors])
if test "x$enable_dependency_tracking" = xno; then
  AMDEP="#"
else
  am_depcomp="$ac_aux_dir/depcomp"
  if test ! -f "$am_depcomp"; then
    AMDEP="#"
  else
    AMDEP=
  fi
fi
AC_SUBST(AMDEP)
if test -z "$AMDEP"; then
  AMDEPBACKSLASH='\'
else
  AMDEPBACKSLASH=
fi
pushdef([subst], defn([AC_SUBST]))
subst(AMDEPBACKSLASH)
popdef([subst])
])