[RFA:] collect2.c: Support not running strip when the ld "-s" option is seen

[Hans-Peter Nilsson <hans-peter dot nilsson at axis dot com>]

The case I use this for is where some executables aren't
strippable after linking, so re-linking with "-s" is how it must
be done.  It's kind of impure magic that collect2 maps "-s" to
"strip" anyway, since "ld -s" *might* mean other things on some
systems.

Bootstrapped on i686-pc-linux-gnu with no regressions with
--disable-libstdcxx-v3, (because that seems the only way to
bootstrap there at the time I started the bootstrap).

Ok to commit?

	* tm.texi (collect2-specific options): Document
	SET_STRIPPABLE_EXECUTABLE.
	* collect2.c (SET_STRIPPABLE_EXECUTABLE): New macro to support not
	mapping "-s" to mean run "strip".

Index: tm.texi
===================================================================
RCS file: /cvs/gcc/egcs/gcc/tm.texi,v
retrieving revision 1.151
diff -c -p -r1.151 tm.texi
*** tm.texi	2000/11/10 05:56:47	1.151
--- tm.texi	2000/11/15 00:38:48
*************** from @code{LDD_SUFFIX}.  If the line lis
*** 6330,6335 ****
--- 6330,6350 ----
  code must advance @var{PTR} to the beginning of the filename on that
  line.  Otherwise, it must set @var{PTR} to @code{NULL}.
  
+ @findex SET_STRIPPABLE_EXECUTABLE
+ @item SET_STRIPPABLE_EXECUTABLE (@var{do_strip}, @var{argc}, @var{argv})
+ This statement macro takes as arguments an @code{int} variable
+ @var{do_strip} and the @var{argc} and @var{argv} seen by the linker.  You
+ should define this macro if @code{strip} is unusable on executables linked
+ with certain linker options on the target system.
+ 
+ When gcc is given the option @code{-s}, the program @code{collect2} will
+ by default only pass it on the to the linker if it needs to re-link files
+ after processing symbol names.  If @code{collect2} finds that it does not
+ need to re-link and this macro is either not defined or sets
+ @var{do_strip} to a non-zero value, it will instead invoke @code{strip}.
+ When @var{do_strip} is set to zero, @code{collect2} will instead re-link
+ with @code{-s}.
+ 
  @end table
  
  @node Instruction Output
Index: collect2.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/collect2.c,v
retrieving revision 1.102
diff -c -p -r1.102 collect2.c
*** collect2.c	2000/11/13 21:22:10	1.102
--- collect2.c	2000/11/15 00:38:49
*************** Boston, MA 02111-1307, USA.  */
*** 139,144 ****
--- 139,150 ----
  
  #endif /* OBJECT_FORMAT_NONE */
  
+ /* Some systems can't use strip on executables when certain options are
+    used; we must then relink instead.  */
+ #ifndef SET_STRIPPABLE_EXECUTABLE
+ #define SET_STRIPPABLE_EXECUTABLE(X, Y, Z)
+ #endif
+ 
  /* Some systems use __main in a way incompatible with its use in gcc, in these
     cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
     give the same symbol without quotes for an alternative entry point.  You
*************** main (argc, argv)
*** 830,835 ****
--- 836,843 ----
       int argc;
       char *argv[];
  {
+   int orig_argc = argc;
+   char **orig_argv = argv;
    const char *ld_suffix	= "ld";
    const char *full_ld_suffix	= ld_suffix;
    const char *real_ld_suffix	= "real-ld";
*************** main (argc, argv)
*** 1198,1204 ****
  		{
  		  /* We must strip after the nm run, otherwise C++ linking
  		     will not work.  Thus we strip in the second ld run, or
! 		     else with strip if there is no second ld run.  */
  		  strip_flag = 1;
  		  ld1--;
  		}
--- 1206,1213 ----
  		{
  		  /* We must strip after the nm run, otherwise C++ linking
  		     will not work.  Thus we strip in the second ld run, or
! 		     else with strip if there is no second ld run.  For
! 		     some systems, we might re-link instead.  */
  		  strip_flag = 1;
  		  ld1--;
  		}
*************** main (argc, argv)
*** 1397,1411 ****
        /* Strip now if it was requested on the command line.  */
        if (strip_flag)
  	{
! 	  char **real_strip_argv = (char **) xcalloc (sizeof (char *), 3);
! 	  const char ** strip_argv = (const char **) real_strip_argv;
! 	  
! 	  strip_argv[0] = strip_file_name;
! 	  strip_argv[1] = output_file;
! 	  strip_argv[2] = (char *) 0;
! 	  fork_execute ("strip", real_strip_argv);
! 	}
  
  #ifdef COLLECT_EXPORT_LIST
        maybe_unlink (export_file);
  #endif
--- 1406,1443 ----
        /* Strip now if it was requested on the command line.  */
        if (strip_flag)
  	{
! 	  int strippable = 1;
! 	  SET_STRIPPABLE_EXECUTABLE (strippable, orig_argc, orig_argv);
! 	  if (strippable)
! 	    {
! 	      char **real_strip_argv = (char **) xcalloc (sizeof (char *), 3);
! 	      const char ** strip_argv = (const char **) real_strip_argv;
  
+ 	      strip_argv[0] = strip_file_name;
+ 	      strip_argv[1] = output_file;
+ 	      strip_argv[2] = (char *) 0;
+ 	      fork_execute ("strip", real_strip_argv);
+ 	    }
+ 	  else
+ 	    {
+ 	      /* If we shouldn't strip, re-link instead.  Delete the
+ 		 file from the previous ld run, so any link failures
+ 		 will not leave an executable with unwanted contents.  */
+ 	      unlink (output_file);
+ 
+ 	      /* Move arguments and put the "-s" argument first in
+ 		 ld1_argv (after the program name); there is room for
+ 		 it.  Note that GNU ld can handle options after files,
+ 		 but we can't rely on it.  We can't use orig_argv
+ 		 because it names collect2 as the program to use, and we
+ 		 can't use ld2_argv, since it contains the "extra"
+ 		 objects.  */
+ 	      memmove (ld1_argv + 2, ld1_argv + 1,
+ 		       ((char **) ld1 + 1 - (ld1_argv + 1)) * sizeof (*ld1));
+ 	      ld1_argv[1] = "-s";
+ 	      fork_execute ("ld", ld1_argv);
+ 	    }
+ 	}
  #ifdef COLLECT_EXPORT_LIST
        maybe_unlink (export_file);
  #endif

brgds, H-P