build: libcody: Link with -lsocket -lnsl if necessary [PR98316]

With the introduction of C++20 modules and libcody, cc1plus and
cc1objplus gained a dependency on the socket functions.  Before those
were merged into libc in Solaris 11.4, one needed to link with -lsocket -lnsl
on Solaris, so that merge broke the Solaris 11.3 build.

While we already have 4 different checks for those libraries in the
tree, I decided to import autoconf-archive's AX_LIB_SOCKET_NSL macro
instead.  At the same time, the patch only links libcody and the
networking libs where needed (cc1plus, cc1objplus).

Bootstrapped without regressions on i386-pc-solaris2.11 (Solaris 11.3
and 11.4), sparc-sun-solaris2.11, and x86_64-pc-linux-gnu.

2020-12-16  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	c++tools:
	PR c++/98316
	* configure.ac: Include ../config/ax_lib_socket_nsl.m4.
	(NETLIBS): Determine using AX_LIB_SOCKET_NSL.
	* configure: Regenerate.
	* Makefile.in (NETLIBS): Define.
	(g++-mapper-server$(exeext)): Add $(NETLIBS).

	gcc/objcp:
	PR c++/98316
	* Make-lang.in (cc1objplus$(exeext)): Add $(CODYLIB), $(NETLIBS).

	gcc/cp:
	PR c++/98316
	* Make-lang.in (cc1plus$(exeext)): Add $(CODYLIB), $(NETLIBS).

	gcc:
	PR c++/98316
	* configure.ac (NETLIBS): Determine using AX_LIB_SOCKET_NSL.
	* aclocal.m4, configure: Regenerate.
	* Makefile.in (NETLIBS): Define.
	(BACKEND): Remove $(CODYLIB).

	config:
	PR c++/98316
	* ax_lib_socket_nsl.m4: Import from autoconf-archive.

3 files changed, 223 insertions, 1 deletions

diff --git a/c++tools/Makefile.in b/c++tools/Makefile.in
index 590a856..9700706 100644
--- a/c++tools/Makefile.in
+++ b/c++tools/Makefile.in
@@ -33,6 +33,7 @@ CXXOPTS := $(CXXFLAGS) $(PIEFLAG) -fno-exceptions -fno-rtti
 LDFLAGS := @LDFLAGS@
 exeext := @EXEEXT@
 LIBIBERTY := ../libiberty/libiberty.a
+NETLIBS := @NETLIBS@
 VERSION.O := ../gcc/version.o
 
 all::
@@ -90,7 +91,7 @@ MAPPER.O := server.o resolver.o
 CODYLIB = ../libcody/libcody.a
 CXXINC += -I$(srcdir)/../libcody -I$(srcdir)/../include -I$(srcdir)/../gcc -I.
 g++-mapper-server$(exeext): $(MAPPER.O) $(CODYLIB)
-	+$(CXX) $(LDFLAGS) $(PIEFLAG) -o $@ $^ $(VERSION.O) $(LIBIBERTY)
+	+$(CXX) $(LDFLAGS) $(PIEFLAG) -o $@ $^ $(VERSION.O) $(LIBIBERTY) $(NETLIBS)
 
 # copy to gcc dir so tests there can run
 all::../gcc/g++-mapper-server$(exeext)
diff --git a/c++tools/configure b/c++tools/configure
index 89441f5..3f511b2 100755
--- a/c++tools/configure
+++ b/c++tools/configure
@@ -622,6 +622,7 @@ ac_includes_default="\
 
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
+NETLIBS
 get_gcc_base_ver
 EGREP
 GREP
@@ -1703,6 +1704,52 @@ $as_echo "$ac_res" >&6; }
   eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
 
 } # ac_fn_c_check_header_compile
+
+# ac_fn_c_try_link LINENO
+# -----------------------
+# Try to link conftest.$ac_ext, and return whether this succeeded.
+ac_fn_c_try_link ()
+{
+  as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
+  rm -f conftest.$ac_objext conftest$ac_exeext
+  if { { ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
+$as_echo "$ac_try_echo"; } >&5
+  (eval "$ac_link") 2>conftest.err
+  ac_status=$?
+  if test -s conftest.err; then
+    grep -v '^ *+' conftest.err >conftest.er1
+    cat conftest.er1 >&5
+    mv -f conftest.er1 conftest.err
+  fi
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext && {
+	 test "$cross_compiling" = yes ||
+	 test -x conftest$ac_exeext
+       }; then :
+  ac_retval=0
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_retval=1
+fi
+  # Delete the IPA/IPO (Inter Procedural Analysis/Optimization) information
+  # created by the PGI compiler (conftest_ipa8_conftest.oo), as it would
+  # interfere with the next link command; also delete a directory that is
+  # left behind by Apple's compiler.  We do this before executing the actions.
+  rm -rf conftest.dSYM conftest_ipa8_conftest.oo
+  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
+  as_fn_set_status $ac_retval
+
+} # ac_fn_c_try_link
 cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
@@ -4242,6 +4289,170 @@ fi
 
 
 
+# Solaris needs libsocket and libnsl for socket functions before 11.4.
+# libcody uses those.
+save_LIBS="$LIBS"
+LIBS=
+
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing gethostbyname" >&5
+$as_echo_n "checking for library containing gethostbyname... " >&6; }
+if ${ac_cv_search_gethostbyname+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_func_search_save_LIBS=$LIBS
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char gethostbyname ();
+int
+main ()
+{
+return gethostbyname ();
+  ;
+  return 0;
+}
+_ACEOF
+for ac_lib in '' nsl; do
+  if test -z "$ac_lib"; then
+    ac_res="none required"
+  else
+    ac_res=-l$ac_lib
+    LIBS="-l$ac_lib  $ac_func_search_save_LIBS"
+  fi
+  if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_search_gethostbyname=$ac_res
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext
+  if ${ac_cv_search_gethostbyname+:} false; then :
+  break
+fi
+done
+if ${ac_cv_search_gethostbyname+:} false; then :
+
+else
+  ac_cv_search_gethostbyname=no
+fi
+rm conftest.$ac_ext
+LIBS=$ac_func_search_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_gethostbyname" >&5
+$as_echo "$ac_cv_search_gethostbyname" >&6; }
+ac_res=$ac_cv_search_gethostbyname
+if test "$ac_res" != no; then :
+  test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
+
+fi
+
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing socket" >&5
+$as_echo_n "checking for library containing socket... " >&6; }
+if ${ac_cv_search_socket+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_func_search_save_LIBS=$LIBS
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char socket ();
+int
+main ()
+{
+return socket ();
+  ;
+  return 0;
+}
+_ACEOF
+for ac_lib in '' socket; do
+  if test -z "$ac_lib"; then
+    ac_res="none required"
+  else
+    ac_res=-l$ac_lib
+    LIBS="-l$ac_lib  $ac_func_search_save_LIBS"
+  fi
+  if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_search_socket=$ac_res
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext
+  if ${ac_cv_search_socket+:} false; then :
+  break
+fi
+done
+if ${ac_cv_search_socket+:} false; then :
+
+else
+  ac_cv_search_socket=no
+fi
+rm conftest.$ac_ext
+LIBS=$ac_func_search_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_socket" >&5
+$as_echo "$ac_cv_search_socket" >&6; }
+ac_res=$ac_cv_search_socket
+if test "$ac_res" != no; then :
+  test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
+
+else
+
+		{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for socket in -lsocket" >&5
+$as_echo_n "checking for socket in -lsocket... " >&6; }
+if ${ac_cv_lib_socket_socket+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lsocket -lnsl $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char socket ();
+int
+main ()
+{
+return socket ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_socket_socket=yes
+else
+  ac_cv_lib_socket_socket=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_socket_socket" >&5
+$as_echo "$ac_cv_lib_socket_socket" >&6; }
+if test "x$ac_cv_lib_socket_socket" = xyes; then :
+  LIBS="-lsocket -lnsl $LIBS"
+fi
+
+fi
+
+
+NETLIBS="$LIBS"
+LIBS="$save_LIBS"
+
+
 ac_config_headers="$ac_config_headers config.h"
 
 ac_config_files="$ac_config_files Makefile"
diff --git a/c++tools/configure.ac b/c++tools/configure.ac
index 1100dc2..5771f2a 100644
--- a/c++tools/configure.ac
+++ b/c++tools/configure.ac
@@ -22,6 +22,7 @@
 # By default g++ uses an in-process mapper.
 
 sinclude(../config/acx.m4)
+sinclude(../config/ax_lib_socket_nsl.m4)
 
 AC_INIT(c++tools)
 
@@ -218,6 +219,15 @@ fi
 # Determine what GCC version number to use in filesystem paths.
 GCC_BASE_VER
 
+# Solaris needs libsocket and libnsl for socket functions before 11.4.
+# libcody uses those.
+save_LIBS="$LIBS"
+LIBS=
+AX_LIB_SOCKET_NSL
+NETLIBS="$LIBS"
+LIBS="$save_LIBS"
+AC_SUBST(NETLIBS)
+
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_FILES([Makefile])