From: Joel Brobecker <brobecker@gnat.com>
Date: Mon, 19 Dec 2011 04:36:29 +0000 (+0000)
Subject: try ignoring bad PLT entries in ELF symbol tables
X-Git-Tag: sid-snapshot-20120101~81
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=828cfa8d0b07fdae7502ee975092a46db4436f5b;p=thirdparty%2Fbinutils-gdb.git

try ignoring bad PLT entries in ELF symbol tables

Comment says it all:

         /* On ia64-hpux, we have discovered that the system linker
            adds undefined symbols with nonzero addresses that cannot
            be right (their address points inside the code of another
            function in the .text section).  This creates problems
            when trying to determine which symbol corresponds to
            a given address.

            We try to detect those buggy symbols by checking which
            section we think they correspond to.  Normally, PLT symbols
            are stored inside their own section, and the typical name
            for that section is ".plt".  So, if there is a ".plt"
            section, and yet the section name of our symbol does not
            start with ".plt", we ignore that symbol.  */

gdb/ChangeLog:

        * elfread.c (elf_symtab_read): Ignore undefined symbols with
        nonzero addresses if they do not correspond to a .plt section
        when one is available in the objfile.
---

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 5a8eb1c0647..68267a31545 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,9 @@
+2011-12-19  Joel Brobecker  <brobecker@adacore.com>
+
+	* elfread.c (elf_symtab_read): Ignore undefined symbols with
+	nonzero addresses if they do not correspond to a .plt section
+	when one is available in the objfile.
+
 2011-12-17  Andreas Schwab  <schwab@linux-m68k.org>
 
 	* cp-name-parser.y (cp_merge_demangle_parse_infos): Don't use
diff --git a/gdb/elfread.c b/gdb/elfread.c
index 067c77f26dc..fd65ecf9159 100644
--- a/gdb/elfread.c
+++ b/gdb/elfread.c
@@ -303,6 +303,23 @@ elf_symtab_read (struct objfile *objfile, int type,
 	  if (!sect)
 	    continue;
 
+	  /* On ia64-hpux, we have discovered that the system linker
+	     adds undefined symbols with nonzero addresses that cannot
+	     be right (their address points inside the code of another
+	     function in the .text section).  This creates problems
+	     when trying to determine which symbol corresponds to
+	     a given address.
+
+	     We try to detect those buggy symbols by checking which
+	     section we think they correspond to.  Normally, PLT symbols
+	     are stored inside their own section, and the typical name
+	     for that section is ".plt".  So, if there is a ".plt"
+	     section, and yet the section name of our symbol does not
+	     start with ".plt", we ignore that symbol.  */
+	  if (strncmp (sect->name, ".plt", 4) != 0
+	      && bfd_get_section_by_name (abfd, ".plt") != NULL)
+	    continue;
+
 	  symaddr += ANOFFSET (objfile->section_offsets, sect->index);
 
 	  msym = record_minimal_symbol