[2/7] gdb, gdbserver: require gcc-style dependency generation, drop the depcomp fallback

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index c6bfc2949fcc..5741ee5e2e92 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -103,9 +103,7 @@  CXX = @CXX@
 CXX_DIALECT = @CXX_DIALECT@
 
 # Dependency tracking information.
-DEPMODE = @CCDEPMODE@
 DEPDIR = @DEPDIR@
-depcomp = $(SHELL) $(srcdir)/../depcomp
 
 # Directory containing source files.
 srcdir = @srcdir@
@@ -114,11 +112,14 @@  top_srcdir = @top_srcdir@
 
 include $(srcdir)/silent-rules.mk
 
-# Note that these are overridden by GNU make-specific code below if
-# GNU make is used.  The overrides implement dependency tracking.
+# Note that we put the dependencies into a .Tpo file, then move them into
+# place if the compile succeeds.  We need this because gcc does not
+# atomically write the dependency output file.
 COMPILE.pre = $(CXX) -x c++ $(CXX_DIALECT)
-COMPILE.post = -c -o $@
-POSTCOMPILE = @true
+COMPILE.post = -c -o $@ \
+	-MT $@ -MMD -MP -MF $(@D)/$(DEPDIR)/$(basename $(@F)).Tpo
+POSTCOMPILE = @mv $(@D)/$(DEPDIR)/$(basename $(@F)).Tpo \
+	$(@D)/$(DEPDIR)/$(basename $(@F)).Po
 
 # CXXFLAGS is at the very end on purpose, so that user-supplied flags can
 # override internal flags.
@@ -2828,23 +2829,6 @@  all_gdbtk_cflags = $(IDE_CFLAGS) $(ITCL_CFLAGS) \
 # Dependency tracking.
 #
 
-ifeq ($(DEPMODE),depmode=gcc3)
-# Note that we put the dependencies into a .Tpo file, then move them
-# into place if the compile succeeds.  We need this because gcc does
-# not atomically write the dependency output file.
-override COMPILE.post = -c -o $@ -MT $@ -MMD -MP \
-	-MF $(@D)/$(DEPDIR)/$(basename $(@F)).Tpo
-override POSTCOMPILE = @mv $(@D)/$(DEPDIR)/$(basename $(@F)).Tpo \
-	$(@D)/$(DEPDIR)/$(basename $(@F)).Po
-else
-override COMPILE.pre = source='$<' object='$@' libtool=no \
-	DEPDIR=$(DEPDIR) $(DEPMODE) $(depcomp) \
-	$(CXX) -x c++ $(CXX_DIALECT)
-# depcomp handles atomicity for us, so we don't need a postcompile
-# step.
-override POSTCOMPILE =
-endif
-
 # A list of all the objects we might care about in this build, for
 # dependency tracking.
 all_object_files = gdb.o $(LIBGDB_OBS) gdbtk/generic/gdbtk-main.o
diff --git a/gdb/configure b/gdb/configure
index 7dc7781cb09f..94cc893a8715 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -795,7 +795,6 @@  SET_MAKE
 PKG_CONFIG_LIBDIR
 PKG_CONFIG_PATH
 PKG_CONFIG
-CCDEPMODE
 DEPDIR
 am__leading_dot
 LTLIBXXHASH
@@ -11878,7 +11877,7 @@  else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11881 "configure"
+#line 11880 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11984,7 +11983,7 @@  else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11987 "configure"
+#line 11986 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -22700,102 +22699,6 @@  DEPDIR="${am__leading_dot}deps"
 ac_config_commands="$ac_config_commands depdir"
 
 
-depcc="$CC"   am_compiler_list=
-
-am_depcomp=$ac_aux_dir/depcomp
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
-$as_echo_n "checking dependency style of $depcc... " >&6; }
-if ${am_cv_CC_dependencies_compiler_type+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -f "$am_depcomp"; then
-  # We make a subdir and do the tests there.  Otherwise we can end up
-  # making bogus files that we don't know about and never remove.  For
-  # instance it was reported that on HP-UX the gcc test will end up
-  # making a dummy file named `D' -- because `-MD' means `put the output
-  # in D'.
-  mkdir conftest.dir
-  # Copy depcomp to subdir because otherwise we won't find it if we're
-  # using a relative directory.
-  cp "$am_depcomp" conftest.dir
-  cd conftest.dir
-  # We will build objects and dependencies in a subdirectory because
-  # it helps to detect inapplicable dependency modes.  For instance
-  # both Tru64's cc and ICC support -MD to output dependencies as a
-  # side effect of compilation, but ICC will put the dependencies in
-  # the current directory while Tru64 will put them in the object
-  # directory.
-  mkdir sub
-
-  am_cv_CC_dependencies_compiler_type=none
-  if test "$am_compiler_list" = ""; then
-     am_compiler_list=`sed -n 's/^\([a-zA-Z0-9]*\))$/\1/p' < ./depcomp`
-  fi
-  for depmode in $am_compiler_list; do
-    if test $depmode = none; then break; fi
-
-    $as_echo "$as_me:$LINENO: trying $depmode" >&5
-    # Setup a source with many dependencies, because some compilers
-    # like to wrap large dependency lists on column 80 (with \), and
-    # we should not choose a depcomp mode which is confused by this.
-    #
-    # We need to recreate these files for each test, as the compiler may
-    # overwrite some of them when testing with obscure command lines.
-    # This happens at least with the AIX C compiler.
-    : > sub/conftest.c
-    for i in 1 2 3 4 5 6; do
-      echo '#include "conftst'$i'.h"' >> sub/conftest.c
-      # Using `: > sub/conftst$i.h' creates only sub/conftst1.h with
-      # Solaris 8's {/usr,}/bin/sh.
-      touch sub/conftst$i.h
-    done
-    echo "include sub/conftest.Po" > confmf
-
-    # We check with `-c' and `-o' for the sake of the "dashmstdout"
-    # mode.  It turns out that the SunPro C++ compiler does not properly
-    # handle `-M -o', and we need to detect this.
-    depcmd="depmode=$depmode \
-       source=sub/conftest.c object=sub/conftest.${OBJEXT-o} \
-       depfile=sub/conftest.Po tmpdepfile=sub/conftest.TPo \
-       $SHELL ./depcomp $depcc -c -o sub/conftest.${OBJEXT-o} sub/conftest.c"
-    echo "| $depcmd" | sed -e 's/  */ /g' >&5
-    if env $depcmd > conftest.err 2>&1 &&
-       grep sub/conftst6.h sub/conftest.Po >>conftest.err 2>&1 &&
-       grep sub/conftest.${OBJEXT-o} sub/conftest.Po >>conftest.err 2>&1 &&
-       ${MAKE-make} -s -f confmf >>conftest.err 2>&1; then
-      # icc doesn't choke on unknown options, it will just issue warnings
-      # or remarks (even with -Werror).  So we grep stderr for any message
-      # that says an option was ignored or not supported.
-      # When given -MP, icc 7.0 and 7.1 complain thusly:
-      #   icc: Command line warning: ignoring option '-M'; no argument required
-      # The diagnosis changed in icc 8.0:
-      #   icc: Command line remark: option '-MP' not supported
-      if (grep 'ignoring option' conftest.err ||
-          grep 'not supported' conftest.err) >/dev/null 2>&1; then :; else
-        am_cv_CC_dependencies_compiler_type=$depmode
-	$as_echo "$as_me:$LINENO: success" >&5
-        break
-      fi
-    fi
-    $as_echo "$as_me:$LINENO: failure, diagnostics are:" >&5
-    sed -e 's/^/| /' < conftest.err >&5
-  done
-
-  cd ..
-  rm -rf conftest.dir
-else
-  am_cv_CC_dependencies_compiler_type=none
-fi
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_CC_dependencies_compiler_type" >&5
-$as_echo "$am_cv_CC_dependencies_compiler_type" >&6; }
-if test x${am_cv_CC_dependencies_compiler_type-none} = xnone
-then as_fn_error $? "no usable dependency style found" "$LINENO" 5
-else CCDEPMODE=depmode=$am_cv_CC_dependencies_compiler_type
-
-fi
-
 
 # Since the first call to PKG_CHECK_MODULES may not happen (is guarded by
 # a condition), we must call PKG_PROG_PKG_CONFIG explicitly to probe for
diff --git a/gdb/configure.ac b/gdb/configure.ac
index c70aa30fc96a..d8b2498f415b 100644
--- a/gdb/configure.ac
+++ b/gdb/configure.ac
@@ -61,7 +61,6 @@  GDB_AC_COMMON
 
 # Dependency checking.
 ZW_CREATE_DEPDIR
-ZW_PROG_COMPILER_DEPENDENCIES([CC])
 
 # Since the first call to PKG_CHECK_MODULES may not happen (is guarded by
 # a condition), we must call PKG_PROG_PKG_CONFIG explicitly to probe for
diff --git a/gdbserver/Makefile.in b/gdbserver/Makefile.in
index e45c89dc321d..b06e0b86e45b 100644
--- a/gdbserver/Makefile.in
+++ b/gdbserver/Makefile.in
@@ -48,9 +48,7 @@  AR_FLAGS = rc
 STRIP = @STRIP@
 
 # Dependency tracking information.
-DEPMODE = @CCDEPMODE@
 DEPDIR = @DEPDIR@
-depcomp = $(SHELL) $(srcdir)/../depcomp
 
 # Directory containing source files.  Don't clean up the spacing,
 # this exact string is matched for by the "configure" script.
@@ -63,11 +61,14 @@  top_builddir = .
 
 include $(srcdir)/../gdb/silent-rules.mk
 
-# Note that these are overridden by GNU make-specific code below if
-# GNU make is used.  The overrides implement dependency tracking.
+# Note that we put the dependencies into a .Tpo file, then move them into
+# place if the compile succeeds.  We need this because gcc does not
+# atomically write the dependency output file.
 COMPILE.pre = $(CXX) $(CXX_DIALECT)
-COMPILE.post = -c -o $@
-POSTCOMPILE = @true
+COMPILE.post = -c -o $@ \
+	-MT $@ -MMD -MP -MF $(@D)/$(DEPDIR)/$(basename $(@F)).Tpo
+POSTCOMPILE = @mv $(@D)/$(DEPDIR)/$(basename $(@F)).Tpo \
+	$(@D)/$(DEPDIR)/$(basename $(@F)).Po
 
 INCLUDE_SERVER_H = -include $(srcdir)/server.h
 
@@ -596,23 +597,6 @@  gdbreplay.o: gdbreplay.cc
 # Dependency tracking.
 #
 
-ifeq ($(DEPMODE),depmode=gcc3)
-# Note that we put the dependencies into a .Tpo file, then move them
-# into place if the compile succeeds.  We need this because gcc does
-# not atomically write the dependency output file.
-override COMPILE.post = -c -o $@ -MT $@ -MMD -MP \
-	-MF $(@D)/$(DEPDIR)/$(basename $(@F)).Tpo
-override POSTCOMPILE = @mv $(@D)/$(DEPDIR)/$(basename $(@F)).Tpo \
-	$(@D)/$(DEPDIR)/$(basename $(@F)).Po
-else
-override COMPILE.pre = source='$<' object='$@' libtool=no \
-	DEPDIR=$(DEPDIR) $(DEPMODE) $(depcomp) \
-	$(CXX) $(CXX_DIALECT)
-# depcomp handles atomicity for us, so we don't need a postcompile
-# step.
-override POSTCOMPILE =
-endif
-
 # A list of all the objects we might care about in this build, for
 # dependency tracking.
 all_object_files = $(OBS) $(GDBREPLAY_OBS) $(IPA_OBJS)
diff --git a/gdbserver/configure b/gdbserver/configure
index 46faecc3a207..3cf8df2c3ae1 100755
--- a/gdbserver/configure
+++ b/gdbserver/configure
@@ -637,7 +637,6 @@  REPORT_BUGS_TO
 PKGVERSION
 WERROR_CFLAGS
 WARN_CFLAGS
-CCDEPMODE
 CONFIG_SRC_SUBDIR
 CATOBJEXT
 GENCAT
@@ -12821,103 +12820,6 @@  CONFIG_SRC_SUBDIR="arch gdbsupport nat target"
 ac_config_commands="$ac_config_commands gdbdepdir"
 
 
-depcc="$CC"   am_compiler_list=
-
-am_depcomp=$ac_aux_dir/depcomp
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
-$as_echo_n "checking dependency style of $depcc... " >&6; }
-if ${am_cv_CC_dependencies_compiler_type+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -f "$am_depcomp"; then
-  # We make a subdir and do the tests there.  Otherwise we can end up
-  # making bogus files that we don't know about and never remove.  For
-  # instance it was reported that on HP-UX the gcc test will end up
-  # making a dummy file named `D' -- because `-MD' means `put the output
-  # in D'.
-  mkdir conftest.dir
-  # Copy depcomp to subdir because otherwise we won't find it if we're
-  # using a relative directory.
-  cp "$am_depcomp" conftest.dir
-  cd conftest.dir
-  # We will build objects and dependencies in a subdirectory because
-  # it helps to detect inapplicable dependency modes.  For instance
-  # both Tru64's cc and ICC support -MD to output dependencies as a
-  # side effect of compilation, but ICC will put the dependencies in
-  # the current directory while Tru64 will put them in the object
-  # directory.
-  mkdir sub
-
-  am_cv_CC_dependencies_compiler_type=none
-  if test "$am_compiler_list" = ""; then
-     am_compiler_list=`sed -n 's/^\([a-zA-Z0-9]*\))$/\1/p' < ./depcomp`
-  fi
-  for depmode in $am_compiler_list; do
-    if test $depmode = none; then break; fi
-
-    $as_echo "$as_me:$LINENO: trying $depmode" >&5
-    # Setup a source with many dependencies, because some compilers
-    # like to wrap large dependency lists on column 80 (with \), and
-    # we should not choose a depcomp mode which is confused by this.
-    #
-    # We need to recreate these files for each test, as the compiler may
-    # overwrite some of them when testing with obscure command lines.
-    # This happens at least with the AIX C compiler.
-    : > sub/conftest.c
-    for i in 1 2 3 4 5 6; do
-      echo '#include "conftst'$i'.h"' >> sub/conftest.c
-      # Using `: > sub/conftst$i.h' creates only sub/conftst1.h with
-      # Solaris 8's {/usr,}/bin/sh.
-      touch sub/conftst$i.h
-    done
-    echo "include sub/conftest.Po" > confmf
-
-    # We check with `-c' and `-o' for the sake of the "dashmstdout"
-    # mode.  It turns out that the SunPro C++ compiler does not properly
-    # handle `-M -o', and we need to detect this.
-    depcmd="depmode=$depmode \
-       source=sub/conftest.c object=sub/conftest.${OBJEXT-o} \
-       depfile=sub/conftest.Po tmpdepfile=sub/conftest.TPo \
-       $SHELL ./depcomp $depcc -c -o sub/conftest.${OBJEXT-o} sub/conftest.c"
-    echo "| $depcmd" | sed -e 's/  */ /g' >&5
-    if env $depcmd > conftest.err 2>&1 &&
-       grep sub/conftst6.h sub/conftest.Po >>conftest.err 2>&1 &&
-       grep sub/conftest.${OBJEXT-o} sub/conftest.Po >>conftest.err 2>&1 &&
-       ${MAKE-make} -s -f confmf >>conftest.err 2>&1; then
-      # icc doesn't choke on unknown options, it will just issue warnings
-      # or remarks (even with -Werror).  So we grep stderr for any message
-      # that says an option was ignored or not supported.
-      # When given -MP, icc 7.0 and 7.1 complain thusly:
-      #   icc: Command line warning: ignoring option '-M'; no argument required
-      # The diagnosis changed in icc 8.0:
-      #   icc: Command line remark: option '-MP' not supported
-      if (grep 'ignoring option' conftest.err ||
-          grep 'not supported' conftest.err) >/dev/null 2>&1; then :; else
-        am_cv_CC_dependencies_compiler_type=$depmode
-	$as_echo "$as_me:$LINENO: success" >&5
-        break
-      fi
-    fi
-    $as_echo "$as_me:$LINENO: failure, diagnostics are:" >&5
-    sed -e 's/^/| /' < conftest.err >&5
-  done
-
-  cd ..
-  rm -rf conftest.dir
-else
-  am_cv_CC_dependencies_compiler_type=none
-fi
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_CC_dependencies_compiler_type" >&5
-$as_echo "$am_cv_CC_dependencies_compiler_type" >&6; }
-if test x${am_cv_CC_dependencies_compiler_type-none} = xnone
-then as_fn_error $? "no usable dependency style found" "$LINENO" 5
-else CCDEPMODE=depmode=$am_cv_CC_dependencies_compiler_type
-
-fi
-
-
 for ac_header in  \
   arpa/inet.h \
   fcntl.h \
diff --git a/gdbserver/configure.ac b/gdbserver/configure.ac
index 9979afe7ece9..a549a8712fc1 100644
--- a/gdbserver/configure.ac
+++ b/gdbserver/configure.ac
@@ -76,8 +76,6 @@  AC_CONFIG_COMMANDS([gdbdepdir],[
   done],
   [ac_aux_dir=$ac_aux_dir DEPDIR=$DEPDIR CONFIG_SRC_SUBDIR="$CONFIG_SRC_SUBDIR"])
 
-ZW_PROG_COMPILER_DEPENDENCIES([CC])
-
 AC_CHECK_HEADERS([ \
   arpa/inet.h \
   fcntl.h \