[binutils-gdb] Generic configury support for shared libs on VxWorks

[Alan Modra <amodra@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f34b00a4362dd9bd6a05ca796d40e42656291d23

commit f34b00a4362dd9bd6a05ca796d40e42656291d23
Author: Olivier Hainque <hainque@adacore.com>
Date:   Mon Aug 7 13:07:33 2023 +0200

    Generic configury support for shared libs on VxWorks
    
    This change adds the configury bits to activate the build of
    shared libs on VxWorks ports configured with --enable-shared,
    for libraries variants where this is generally supported (rtp,
    code model !large - currently not compatible with -fPIC).
    
    Set lt_cv_deplibs_check_method in libtool.m4, so the build of
    libraries know how to establish dependencies.  This is useful in
    configurations such as aarch64 where proper support of LSE relies
    on accurate dependency information between libstdc++ and libgcc_s
    to begin with.
    
            * libtool.m4 (*vxworks*): When enable_shared, set dynamic_linker
            and friends for rtp !large. Assume the linker has the required
            abilities and set lt_cv_deplibs_check_method.

Diff:
---
 libtool.m4 | 29 +++++++++++++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/libtool.m4 b/libtool.m4
index cb502dabe83..8c8399f600e 100644
--- a/libtool.m4
+++ b/libtool.m4
@@ -2700,6 +2700,25 @@ uts4*)
   shlibpath_var=LD_LIBRARY_PATH
   ;;
 
+# Shared libraries for VwWorks, >= 7 only at this stage
+# and (fpic) still incompatible with "large" code models
+# in a few configurations. Only for RTP mode in any case,
+# and upon explicit request at configure time.
+vxworks7*)
+  dynamic_linker=no
+  case ${with_multisubdir}-${enable_shared} in
+    *large*)
+      ;;
+    *mrtp*-yes)
+      version_type=linux
+      need_lib_prefix=no
+      need_version=no
+      library_names_spec='${libname}${release}${shared_ext}$versuffix ${libname}${release}${shared_ext}$major $libname${shared_ext}'
+      soname_spec='${libname}${release}${shared_ext}$major'
+      dynamic_linker="$host_os module_loader"
+      ;;
+  esac
+  ;;
 *)
   dynamic_linker=no
   ;;
@@ -3187,6 +3206,11 @@ sysv4 | sysv4.3*)
 tpf*)
   lt_cv_deplibs_check_method=pass_all
   ;;
+vxworks*)
+  # Assume VxWorks cross toolchains are built on Linux, possibly
+  # as canadian for Windows hosts.
+  lt_cv_deplibs_check_method=pass_all
+  ;;
 esac
 ])
 file_magic_cmd=$lt_cv_file_magic_cmd
@@ -6429,8 +6453,9 @@ if test "$_lt_caught_CXX_error" != yes; then
         ;;
 
       vxworks*)
-        # FIXME: insert proper C++ library support
-        _LT_TAGVAR(ld_shlibs, $1)=no
+        # For VxWorks ports, we assume the use of a GNU linker with
+        # standard elf conventions.
+        _LT_TAGVAR(ld_shlibs, $1)=yes
         ;;
 
       *)