Implement ld --print-output-format.

6 files changed, 32 insertions, 2 deletions

diff --git a/ld/ChangeLog b/ld/ChangeLog
index 768d2bb..220ffe5 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,14 @@
+2011-07-16  Roland McGrath  <roland@hack.frob.com>
+
+	* ld.h (args_type): New field print_output_format.
+	* lexsup.c (enum option_values, ld_options, parse_args):
+	Handle --print-output-format.
+	* ldmain.c (main): Implement --print-output-format.
+	* ld.texinfo (Options): Document it.
+
+	* ldlang.c (lang_get_output_target): Don't return current_target
+	when it's NULL.
+
 2011-07-15  Alan Modra  <amodra@gmail.com>
 
 	* Makefile.am (e*.c): Sort.
diff --git a/ld/ld.h b/ld/ld.h
index 996cdd2..a18b265 100644
--- a/ld/ld.h
+++ b/ld/ld.h
@@ -200,6 +200,9 @@ typedef struct {
      input files.  */
   bfd_boolean accept_unknown_input_arch;
 
+  /* If TRUE we'll just print the default output on stdout.  */
+  bfd_boolean print_output_format;
+
   /* Big or little endian as set on command line.  */
   enum endian_enum endian;
 
diff --git a/ld/ld.texinfo b/ld/ld.texinfo
index 4fb649a..7547c0a5 100644
--- a/ld/ld.texinfo
+++ b/ld/ld.texinfo
@@ -1401,6 +1401,13 @@ default behaviour (of not listing the sections that are removed) can
 be restored by specifying @samp{--no-print-gc-sections} on the command
 line.
 
+@kindex --print-output-format
+@cindex output format
+@item --print-output-format
+Print the name of the default output format (perhaps influenced by
+other command-line options).  This is the string that would appear
+in an @code{OUTPUT_FORMAT} linker script command (@pxref{File Commands}).
+
 @cindex help
 @cindex usage
 @kindex --help
diff --git a/ld/ldlang.c b/ld/ldlang.c
index 3e63eed..0ffafb6 100644
--- a/ld/ldlang.c
+++ b/ld/ldlang.c
@@ -3052,7 +3052,7 @@ lang_get_output_target (void)
 
   /* No - has the current target been set to something other than
      the default?  */
-  if (current_target != default_target)
+  if (current_target != default_target && current_target != NULL)
     return current_target;
 
   /* No - can we determine the format of the first input file?  */
diff --git a/ld/ldmain.c b/ld/ldmain.c
index 1b4afff..ec9dcff 100644
--- a/ld/ldmain.c
+++ b/ld/ldmain.c
@@ -427,11 +427,14 @@ main (int argc, char **argv)
       info_msg ("\n==================================================\n");
     }
 
+  if (command_line.print_output_format)
+    info_msg ("%s\n", lang_get_output_target ());
+
   lang_final ();
 
   if (!lang_has_input_file)
     {
-      if (version_printed)
+      if (version_printed || command_line.print_output_format)
 	xexit (0);
       einfo (_("%P%F: no input files\n"));
     }
diff --git a/ld/lexsup.c b/ld/lexsup.c
index 08ef107..b5e52a8 100644
--- a/ld/lexsup.c
+++ b/ld/lexsup.c
@@ -175,6 +175,7 @@ enum option_values
   OPTION_PLUGIN_OPT,
 #endif /* ENABLE_PLUGINS */
   OPTION_DEFAULT_SCRIPT,
+  OPTION_PRINT_OUTPUT_FORMAT,
 };
 
 /* The long options.  This structure is used for both the option
@@ -491,6 +492,8 @@ static const struct ld_option ld_options[] =
   { {"oformat", required_argument, NULL, OPTION_OFORMAT},
     '\0', N_("TARGET"), N_("Specify target of output file"),
     EXACTLY_TWO_DASHES },
+  { {"print-output-format", no_argument, NULL, OPTION_PRINT_OUTPUT_FORMAT},
+    '\0', NULL, N_("Print default output format"), TWO_DASHES },
   { {"qmagic", no_argument, NULL, OPTION_IGNORE},
     '\0', NULL, N_("Ignored for Linux compatibility"), ONE_DASH },
   { {"reduce-memory-overheads", no_argument, NULL,
@@ -1059,6 +1062,9 @@ parse_args (unsigned argc, char **argv)
 	case OPTION_OFORMAT:
 	  lang_add_output_format (optarg, NULL, NULL, 0);
 	  break;
+	case OPTION_PRINT_OUTPUT_FORMAT:
+	  command_line.print_output_format = TRUE;
+	  break;
 #ifdef ENABLE_PLUGINS
 	case OPTION_PLUGIN:
 	  if (plugin_opt_plugin (optarg))