[binutils-gdb] Revert: 35fd2ddeb1d90f1750401cfb6d01fe055656b88d

[binutils-gdb] Revert: 35fd2ddeb1d90f1750401cfb6d01fe055656b88d

[Nick Clifton]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=057a2b4c4b57ef495dd32c9087e4af28bda41737

commit 057a2b4c4b57ef495dd32c9087e4af28bda41737
Author: Nick Clifton <nickc@redhat.com>
Date:   Wed Jun 26 13:17:25 2024 +0100

    Revert: 35fd2ddeb1d90f1750401cfb6d01fe055656b88d
    
      PR 20814

Diff:
---
 binutils/dlltool.c                   |  21 ++++--
 binutils/doc/binutils.texi           |   2 +-
 ld/ld.texi                           |  19 ++++++
 ld/ldelf.c                           |   2 +-
 ld/ldfile.c                          |  69 ++++++++++++++------
 ld/ldfile.h                          |  21 ++++--
 ld/ldgram.y                          |   2 +-
 ld/ldlang.h                          |   8 ++-
 ld/lexsup.c                          |   6 +-
 ld/plugin.c                          |  12 +++-
 ld/testsuite/ld-plugin/libdep-a.c    |   7 ++
 ld/testsuite/ld-plugin/libdep-b.c    |   5 ++
 ld/testsuite/ld-plugin/libdep-main.c |   7 ++
 ld/testsuite/ld-plugin/libdep.exp    | 123 +++++++++++++++++++++++++++++++++++
 14 files changed, 265 insertions(+), 39 deletions(-)

diff --git a/binutils/dlltool.c b/binutils/dlltool.c
index 7a3d20f0af9..2c37ad3c6a3 100644
--- a/binutils/dlltool.c
+++ b/binutils/dlltool.c
@@ -784,9 +784,10 @@ typedef struct export
   int ordinal;
   int constant;
   int noname;		/* Don't put name in image file.  */
-  int private;		/* Don't put reference in import lib.  */
+  int private;	/* Don't put reference in import lib.  */
   int data;
-  int forward;		/* Number of forward label, 0 means no forward.  */
+  int hint;
+  int forward;	/* Number of forward label, 0 means no forward.  */
   struct export *next;
 }
 export_type;
@@ -2697,8 +2698,10 @@ make_one_lib_file (export_type *exp, int i, int delay)
 	case IDATA6:
 	  if (!exp->noname)
 	    {
-	      int idx = exp->ordinal;
-
+	      /* This used to add 1 to exp->hint.  I don't know
+		 why it did that, and it does not match what I see
+		 in programs compiled with the MS tools.  */
+	      int idx = exp->hint;
 	      if (exp->its_name)
 	        si->size = strlen (exp->its_name) + 3;
 	      else
@@ -3058,6 +3061,7 @@ gen_lib_file (int delay)
 	  alias_exp.noname = exp->noname;
 	  alias_exp.private = exp->private;
 	  alias_exp.data = exp->data;
+	  alias_exp.hint = exp->hint;
 	  alias_exp.forward = exp->forward;
 	  alias_exp.next = exp->next;
 	  n = make_one_lib_file (&alias_exp, i + PREFIX_ALIAS_BASE, delay);
@@ -3711,8 +3715,10 @@ mangle_defs (void)
 {
   /* First work out the minimum ordinal chosen.  */
   export_type *exp;
-  export_type **d_export_vec = xmalloc (sizeof (export_type *) * d_nfuncs);
+
   int i;
+  int hint = 0;
+  export_type **d_export_vec = xmalloc (sizeof (export_type *) * d_nfuncs);
 
   inform (_("Processing definitions"));
 
@@ -3741,6 +3747,11 @@ mangle_defs (void)
 
   qsort (d_exports_lexically, i, sizeof (export_type *), nfunc);
 
+  /* Fill exp entries with their hint values.  */
+  for (i = 0; i < d_nfuncs; i++)
+    if (!d_exports_lexically[i]->noname || show_allnames)
+      d_exports_lexically[i]->hint = hint++;
+
   inform (_("Processed definitions"));
 }
 
diff --git a/binutils/doc/binutils.texi b/binutils/doc/binutils.texi
index c78c9e393f2..2b13a4bfeb1 100644
--- a/binutils/doc/binutils.texi
+++ b/binutils/doc/binutils.texi
@@ -457,7 +457,7 @@ Specify dependencies of this library.  The dependencies must immediately
 follow this option character, must use the same syntax as the linker
 command line, and must be specified within a single argument.  I.e., if
 multiple items are needed, they must be quoted to form a single command
-line argument.  For example @samp{L "-L/usr/local/lib -lmydep1 -lmydep2"}
+line argument.  For example @samp{l "-L/usr/local/lib -lmydep1 -lmydep2"}
 
 @item N
 Uses the @var{count} parameter.  This is used if there are multiple
diff --git a/ld/ld.texi b/ld/ld.texi
index 2eafeb7dd39..89e3913317a 100644
--- a/ld/ld.texi
+++ b/ld/ld.texi
@@ -7614,6 +7614,7 @@ command line option. @xref{Options}.
 
 @menu
 * libdep Plugin::	Static Library Dependencies Plugin
+* lto Plugin::          LTO Plugin
 @end menu
 
 @node libdep Plugin
@@ -7652,6 +7653,24 @@ the @samp{__.LIBDEP} member of @file{libssl.a} would contain
 -L/usr/local/lib -lcrypto
 @end smallexample
 
+Note any library search directories added in this way are only used to
+search for libraries which are also added the same plugin.  They are
+not used for searching for libraries specified on the linker command
+line, linker scripts or other plugins.  This does however present a
+problem if multiple archives with @samp{__.LIBDEP} entries are present
+as they will all be handled by the libdep plugin and thus they will
+share library search paths.  This could result in a library being
+loaded from an unexpected location.
+
+@node lto Plugin
+@section LTO Plugin
+Although not shipped with the binutils the LTO Plugin from the GCC
+project is nevertheless a plugin that is designed to work with the
+linker.  The plugin intercepts object files as they are loaded by the
+linker and instead sends them to the LTO compiler.  When that compiler
+finishes the resulting object file(s) are passed back to the linker
+for normal processing.
+
 @node Special Sections
 @chapter Special Sections
 When linking ELF format object files @command{ld} treats some sections
diff --git a/ld/ldelf.c b/ld/ldelf.c
index 04045acbf3d..09691609fc0 100644
--- a/ld/ldelf.c
+++ b/ld/ldelf.c
@@ -1170,7 +1170,7 @@ ldelf_handle_dt_needed (struct elf_link_hash_table *htab,
 	    {
 	      char *filename;
 
-	      if (search->cmdline)
+	      if (search->source != search_dir_linker_script)
 		continue;
 	      filename = (char *) xmalloc (strlen (search->name) + len + 2);
 	      sprintf (filename, "%s/%s", search->name, l->name);
diff --git a/ld/ldfile.c b/ld/ldfile.c
index f1107a1b7d7..87be885d31a 100644
--- a/ld/ldfile.c
+++ b/ld/ldfile.c
@@ -40,12 +40,6 @@
 #include "plugin.h"
 #endif /* BFD_SUPPORTS_PLUGINS */
 
-bool ldfile_assumed_script = false;
-const char *ldfile_output_machine_name = "";
-unsigned long ldfile_output_machine;
-enum bfd_architecture ldfile_output_architecture;
-search_dirs_type *search_head;
-
 #ifdef VMS
 static char *slash = "";
 #else
@@ -62,6 +56,12 @@ typedef struct search_arch
   struct search_arch *next;
 } search_arch_type;
 
+bool                   ldfile_assumed_script = false;
+const char *           ldfile_output_machine_name = "";
+unsigned long          ldfile_output_machine;
+enum bfd_architecture  ldfile_output_architecture;
+search_dirs_type *     search_head;
+
 static search_dirs_type **search_tail_ptr = &search_head;
 static search_arch_type *search_arch_head;
 static search_arch_type **search_arch_tail_ptr = &search_arch_head;
@@ -303,21 +303,20 @@ is_sysrooted_pathname (const char *name)
 }
 
 /* Adds NAME to the library search path.
-   Makes a copy of NAME using xmalloc().  */
+   Makes a copy of NAME using xmalloc().
+   Returns a pointer to the newly created search_dirs_type structure
+   or NULL if there was a problem.  */
 
-void
-ldfile_add_library_path (const char *name, bool cmdline)
+search_dirs_type *
+ldfile_add_library_path (const char *name, enum search_dir_source source)
 {
   search_dirs_type *new_dirs;
 
-  if (!cmdline && config.only_cmd_line_lib_dirs)
-    return;
+  if (source != search_dir_cmd_line && config.only_cmd_line_lib_dirs)
+    return NULL;
 
   new_dirs = (search_dirs_type *) xmalloc (sizeof (search_dirs_type));
-  new_dirs->next = NULL;
-  new_dirs->cmdline = cmdline;
-  *search_tail_ptr = new_dirs;
-  search_tail_ptr = &new_dirs->next;
+  new_dirs->source = source;
 
   /* If a directory is marked as honoring sysroot, prepend the sysroot path
      now.  */
@@ -327,6 +326,25 @@ ldfile_add_library_path (const char *name, bool cmdline)
     new_dirs->name = concat (ld_sysroot, name + strlen ("$SYSROOT"), (const char *) NULL);
   else
     new_dirs->name = xstrdup (name);
+
+  /* Accumulate script and command line sourced
+     search paths at the end of the current list.  */
+#if BFD_SUPPORTS_PLUGINS
+  /* PR 31904: But put plugin sourced paths at the start of the list.  */
+  if (source == search_dir_plugin)
+    {
+      new_dirs->next = search_head;
+      search_head = new_dirs;
+    }
+  else
+#endif
+    {
+      new_dirs->next = NULL;
+      *search_tail_ptr = new_dirs;
+      search_tail_ptr = &new_dirs->next;
+    }
+
+  return new_dirs;
 }
 
 /* Try to open a BFD for a lang_input_statement.  */
@@ -352,9 +370,9 @@ ldfile_try_open_bfd (const char *attempt,
       return false;
     }
 
-  /* PR 30568: Do not track lto generated temporary object files.  */
+  /* PR 30568: Do not track plugin generated object files.  */
 #if BFD_SUPPORTS_PLUGINS
-  if (!entry->flags.lto_output)
+  if (entry->plugin != NULL)
 #endif
     track_dependency_files (attempt);
 
@@ -365,7 +383,7 @@ ldfile_try_open_bfd (const char *attempt,
   entry->the_bfd->is_linker_input = 1;
 
 #if BFD_SUPPORTS_PLUGINS
-  if (entry->flags.lto_output)
+  if (entry->plugin != NULL)
     entry->the_bfd->lto_output = 1;
 #endif
 
@@ -576,6 +594,14 @@ ldfile_open_file_search (const char *arch,
     {
       char *string;
 
+#if BFD_SUPPORTS_PLUGINS
+      /* PR 31904: Only check a plugin sourced search
+	 directory if the file is from the same plugin.  */
+      if (search->source == search_dir_plugin
+	  && entry->plugin != search->plugin)
+	continue;
+#endif
+
       if (entry->flags.dynamic && !bfd_link_relocatable (&link_info))
 	{
 	  if (ldemul_open_dynamic_archive (arch, search, entry))
@@ -844,7 +870,7 @@ ldfile_find_command_file (const char *name,
 	{
 	  search_dirs_type **save_tail_ptr = search_tail_ptr;
 	  search_tail_ptr = &script_search;
-	  ldfile_add_library_path (script_dir, true);
+	  (void) ldfile_add_library_path (script_dir, search_dir_cmd_line);
 	  search_tail_ptr = save_tail_ptr;
 	}
     }
@@ -858,6 +884,11 @@ ldfile_find_command_file (const char *name,
        search != NULL;
        search = search->next)
     {
+#if BFD_SUPPORTS_PLUGINS
+      /* Do not search for linker commands in plugin sourced search directories.  */
+      if (search->source == search_dir_plugin)
+	continue;
+#endif
       path = concat (search->name, slash, name, (const char *) NULL);
       result = try_open (path, sysrooted);
       free (path);
diff --git a/ld/ldfile.h b/ld/ldfile.h
index f79abf2310d..08826f65f04 100644
--- a/ld/ldfile.h
+++ b/ld/ldfile.h
@@ -26,6 +26,15 @@ extern unsigned long ldfile_output_machine;
 extern enum bfd_architecture ldfile_output_architecture;
 extern const char *ldfile_output_machine_name;
 
+enum search_dir_source
+{
+  search_dir_cmd_line,
+#if BFD_SUPPORTS_PLUGINS
+  search_dir_plugin,
+#endif
+  search_dir_linker_script
+};
+
 /* Structure used to hold the list of directories to search for
    libraries.  */
 
@@ -35,8 +44,12 @@ typedef struct search_dirs
   struct search_dirs *next;
   /* Name of directory.  */
   const char *name;
-  /* TRUE if this is from the command line.  */
-  bool cmdline;
+  /* Where the search path came from.  */
+  enum search_dir_source source;
+#if BFD_SUPPORTS_PLUGINS
+  /* For search dirs added by plugins, the plugin that added them.  */
+  void * plugin;
+#endif
 } search_dirs_type;
 
 enum script_open_style
@@ -59,8 +72,8 @@ extern search_dirs_type *search_head;
 
 extern void ldfile_add_arch
   (const char *);
-extern void ldfile_add_library_path
-  (const char *, bool cmdline);
+extern search_dirs_type * ldfile_add_library_path
+  (const char *, enum search_dir_source);
 extern void ldfile_open_command_file
   (const char *name);
 extern void ldfile_open_script_file
diff --git a/ld/ldgram.y b/ld/ldgram.y
index 07c19ba8692..7c04025f526 100644
--- a/ld/ldgram.y
+++ b/ld/ldgram.y
@@ -321,7 +321,7 @@ ifile_p1:
 	|	TARGET_K '(' NAME ')'
 		{ lang_add_target($3); }
 	|	SEARCH_DIR '(' filename ')'
-		{ ldfile_add_library_path ($3, false); }
+		{ ldfile_add_library_path ($3, search_dir_linker_script); }
 	|	OUTPUT '(' filename ')'
 		{ lang_add_output($3, 1); }
 	|	OUTPUT_FORMAT '(' NAME ')'
diff --git a/ld/ldlang.h b/ld/ldlang.h
index 4c1bb002f8e..f36e04c586a 100644
--- a/ld/ldlang.h
+++ b/ld/ldlang.h
@@ -293,9 +293,6 @@ struct lang_input_statement_flags
 
   /* Set if the file was claimed from an archive.  */
   unsigned int claim_archive : 1;
-
-  /* Set if added by the lto plugin add_input_file callback.  */
-  unsigned int lto_output : 1;
 #endif /* BFD_SUPPORTS_PLUGINS */
 
   /* Head of list of pushed flags.  */
@@ -332,6 +329,11 @@ typedef struct lang_input_statement_struct
   const char *target;
 
   struct lang_input_statement_flags flags;
+
+#if BFD_SUPPORTS_PLUGINS
+  /* If non-NULL the plugin that added this file.  */
+  void * plugin;
+#endif  
 } lang_input_statement_type;
 
 typedef struct
diff --git a/ld/lexsup.c b/ld/lexsup.c
index 96fb73159bf..4aa0124ce2f 100644
--- a/ld/lexsup.c
+++ b/ld/lexsup.c
@@ -1052,7 +1052,8 @@ parse_args (unsigned argc, char **argv)
 	  xexit (0);
 	  break;
 	case 'L':
-	  ldfile_add_library_path (optarg, true);
+	  /* FIXME: Check the return value ?  */
+	  (void) ldfile_add_library_path (optarg, search_dir_cmd_line);
 	  break;
 	case 'l':
 	  lang_add_input_file (optarg, lang_input_file_is_l_enum, NULL);
@@ -2086,7 +2087,8 @@ set_default_dirlist (char *dirlist_ptr)
       if (p != NULL)
 	*p = '\0';
       if (*dirlist_ptr != '\0')
-	ldfile_add_library_path (dirlist_ptr, true);
+	/* FIXME: Check the return value ?  */
+	(void) ldfile_add_library_path (dirlist_ptr, search_dir_cmd_line);
       if (p == NULL)
 	break;
       dirlist_ptr = p + 1;
diff --git a/ld/plugin.c b/ld/plugin.c
index 13d29d6b09f..8107841407a 100644
--- a/ld/plugin.c
+++ b/ld/plugin.c
@@ -928,7 +928,7 @@ add_input_file (const char *pathname)
 			    NULL);
   if (!is)
     return LDPS_ERR;
-  is->flags.lto_output = 1;
+  is->plugin = called_plugin;
   return LDPS_OK;
 }
 
@@ -943,17 +943,23 @@ add_input_library (const char *pathname)
 			    NULL);
   if (!is)
     return LDPS_ERR;
-  is->flags.lto_output = 1;
+  is->plugin = called_plugin;
   return LDPS_OK;
 }
 
 /* Set the extra library path to be used by libraries added via
    add_input_library.  */
+
 static enum ld_plugin_status
 set_extra_library_path (const char *path)
 {
+  search_dirs_type * sdt;
+
   ASSERT (called_plugin);
-  ldfile_add_library_path (xstrdup (path), false);
+  sdt = ldfile_add_library_path (xstrdup (path), search_dir_plugin);
+  if (sdt == NULL)
+    return LDPS_ERR;
+  sdt->plugin = called_plugin;
   return LDPS_OK;
 }
 
diff --git a/ld/testsuite/ld-plugin/libdep-a.c b/ld/testsuite/ld-plugin/libdep-a.c
new file mode 100644
index 00000000000..5a01ce8c88a
--- /dev/null
+++ b/ld/testsuite/ld-plugin/libdep-a.c
@@ -0,0 +1,7 @@
+extern int g (void);
+
+int
+f (void)
+{
+  return g();
+}
diff --git a/ld/testsuite/ld-plugin/libdep-b.c b/ld/testsuite/ld-plugin/libdep-b.c
new file mode 100644
index 00000000000..d2ca7e08694
--- /dev/null
+++ b/ld/testsuite/ld-plugin/libdep-b.c
@@ -0,0 +1,5 @@
+int
+g (void)
+{
+  return 4;
+}
diff --git a/ld/testsuite/ld-plugin/libdep-main.c b/ld/testsuite/ld-plugin/libdep-main.c
new file mode 100644
index 00000000000..7563a7d5f88
--- /dev/null
+++ b/ld/testsuite/ld-plugin/libdep-main.c
@@ -0,0 +1,7 @@
+extern int f (void);
+
+int
+main (void)
+{
+  return f();
+}
diff --git a/ld/testsuite/ld-plugin/libdep.exp b/ld/testsuite/ld-plugin/libdep.exp
new file mode 100644
index 00000000000..e0afcfc342a
--- /dev/null
+++ b/ld/testsuite/ld-plugin/libdep.exp
@@ -0,0 +1,123 @@
+# Expect script for ld-plugin LIBDEP tests
+#   Copyright (C) 2024 Free Software Foundation, Inc.
+#
+# This file is part of the GNU Binutils.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+# MA 02110-1301, USA.
+
+# These tests require the plugin API.
+if { ![check_plugin_api_available] } {
+    return
+}
+
+# Check to see if the C compiler works
+# FIXME: This is being lazy, we could create assembler equivalents instead.
+if { ![check_compiler_available] } {
+    return
+}
+
+proc run_test { } {
+    global CC_FOR_TARGET
+    global srcdir
+    global subdir
+    global ar
+    global ld
+    global libdep
+    global base_dir
+    
+    set testname "libdep test"
+    
+    # Create temporary directories if they do not already exist.
+    file mkdir -p libdep-a libdep-b
+
+    # Delete old versions of the files we are about to build, just in case.
+    file delete libdep-a/a.o libdep-a/liba.a libdep-b/b.o libdep-b/libc.a libdep-main.o
+
+    # Build object files.
+    if {![ld_compile $CC_FOR_TARGET $srcdir/$subdir/libdep-a.c libdep-a/a.o]} {
+	fail "$testname: could not compile source file 1"
+	return
+    }
+    if {![ld_compile $CC_FOR_TARGET $srcdir/$subdir/libdep-b.c libdep-b/b.o]} {
+	fail "$testname: could not compile source file 2"
+	return
+    }
+    if {![ld_compile $CC_FOR_TARGET $srcdir/$subdir/libdep-main.c libdep-main.o]} {
+	fail "$testname: could not compile source file 3"
+	return
+    }
+
+    # Create static archives from the objects.
+
+    # For the first archive we add a libdep element that loads the second library.
+    if {![ar_simple_create $ar {--record-libdeps "-Llibdep-b -lc"} libdep-a/liba.a libdep-a/a.o]} {
+	fail "$testname: could not create archive 1"
+	return
+    }
+
+    # For the second archive we choose a name - libc.a - that is likely to clash
+    # with a system library.  This will help to check that the library loaded by
+    # following the libdep element in the first library is the one that we expect.
+    if {![ar_simple_create $ar {} libdep-b/libc.a libdep-b/b.o]} {
+	fail "$testname: could not create archive 2"
+	return
+    }
+
+    # Find the libdep plugin.
+    # Use libtool to find the path to the plugin rather
+    # than worrying about run paths or anything like that.
+    catch "exec $base_dir/libtool --config" lt_config
+    verbose "Full lt config: $lt_config" 2
+    # Look for "objdir=.libs"
+    regexp -line "^objdir=.*$" "$lt_config" lt_objdir
+    verbose "lt_objdir line is '$lt_objdir'" 2
+    set lt_objdir [regsub "objdir=" "$lt_objdir" ""]
+
+    if { [ file exists "$base_dir/$lt_objdir/libdep.so" ] } {
+	set libdep "$base_dir/$lt_objdir/libdep.so"
+    } else {
+	# FIXME: Check in the system bfd-plugin directory ?
+	fail "$testname - could not locate libdep plugin"
+    }
+
+    verbose "Full plugin path: $libdep" 1
+    
+    # Link the main object file with the liba.a library.
+    # Use the libdep plugin to read the __.LIBDEP element in the liba.a library
+    # and so bring in the libdep-b.o object file from the libc.a library.
+    # Failure to locate the libc.a library, or loading the wrong libc.a library
+    # will result in an unresolved reference error.
+    set exec_output [run_host_cmd "$ld" "-plugin $libdep -o libdep.exe libdep-main.o -L libdep-a -la -e 0"]
+    set exec_output [prune_warnings $exec_output]
+
+    set expected_output "got deps for library libdep-a/liba.a: -Llibdep-b -lc"
+    
+    if ![string match $expected_output $exec_output] then {
+	fail "$testname: did not get expected output from the linker"
+	return
+    }
+
+    regsub -all "$expected_output" $exec_output "\\1" exec_output
+
+    if {![string match "" $exec_output]} {
+	fail "$testname: unexpected output from linker: $exec_output"
+	return
+    }
+
+    pass "$testname"
+}
+
+run_test