Re: Anyone built Emacs with gcc-3.3?

[Paul Eggert <eggert@twinsun.com>]

I found the other bug that was preventing Emacs 21.3 from building
with GCC 3.3 on Solaris 8 (sparc).  Here is a patch.  When I installed
this patch, together with the patch I sent earlier today, Emacs built
and installed on Solaris 8 with GCC 3.3, and ran OK on some simple
tests.

2003-07-11  Paul Eggert  <eggert@twinsun.com>

	* unexelf.c (unexec): Consider a section to precede the .bss
	section if its addresses overlap that of .bss.  This fixes the
	bug reported by Simon Marshall in
	<http://mail.gnu.org/archive/html/emacs-devel/2003-07/msg00033.html>,
	if you also install the patch that I submitted yesterday in
	<http://mail.gnu.org/archive/html/emacs-devel/2003-07/msg00207.html>.
	This patch is related to my 1996-06-24 patch to unexelf.c
	<http://www.geocrawler.com/archives/3/337/1996/6/0/1851704/>,
	but it uses a more precise heuristic for deciding when the other
	section precedes the .bss section.

--- emacs-21.3/src/unexelf.c	2002-10-15 07:21:44.000000000 -0700
+++ emacs-21.3-fix/src/unexelf.c	2003-07-11 14:59:48.649294000 -0700
@@ -971,8 +971,13 @@ unexec (new_name, old_name, data_start, 
 	}
       else
 	{
-	  /* Any section that was original placed AFTER the bss
-	     section should now be off by NEW_DATA2_SIZE. */
+	  /* Any section that was originally placed after the .bss
+	     section should now be off by NEW_DATA2_SIZE.  If a
+	     section overlaps the .bss section, consider it to be
+	     placed after the .bss section.  Overlap can occur if the
+	     section just before .bss has less-strict alignment; this
+	     was observed between .symtab and .bss on Solaris 2.5.1
+	     (sparc) with GCC snapshot 960602.  */
 #ifdef SOLARIS_POWERPC
 	  /* On PPC Reference Platform running Solaris 2.5.1
 	     the plt section is also of type NOBI like the bss section.
@@ -986,9 +991,8 @@ unexec (new_name, old_name, data_start, 
 	      >= OLD_SECTION_H (old_bss_index-1).sh_offset)
 	    NEW_SECTION_H (nn).sh_offset += new_data2_size;
 #else
-	  if (round_up (NEW_SECTION_H (nn).sh_offset,
-			OLD_SECTION_H (old_bss_index).sh_addralign)
-	      >= new_data2_offset)
+	  if (NEW_SECTION_H (nn).sh_offset + NEW_SECTION_H (nn).sh_size
+	      > new_data2_offset)
 	    NEW_SECTION_H (nn).sh_offset += new_data2_size;
 #endif
 	  /* Any section that was originally placed after the section