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Date: Wed, 20 Jan 2010 16:10:00 -0000
From: "andre dot poenitz at nokia dot com" <sourceware-bugzilla@sourceware.org>
To: gdb-prs@sourceware.org
Message-ID: <20100120161016.11198.andre.poenitz@nokia.com>
Reply-To: sourceware-bugzilla@sourceware.org
Subject: [Bug symtab/11198] New: Performance problem in find_minsym_and_objfile
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Each time I step the first time into code belonging to some library like QtCore
or QtGui, gdb goes to 100% CPU for 10-20 seconds. That time is spent almost
entirely in find_minsym_and_objfile (char *name, struct objfile **objfile_p) in
glibc-tdep.c. The change below removes the delay and does not seem to have ill
side-effects for me.

--- glibc-tdep.c.orig   2010-01-20 16:00:22.000000000 +0100
+++ glibc-tdep.c        2010-01-20 17:04:41.000000000 +0100
@@ -41,15 +41,12 @@
   ALL_OBJFILES (objfile)
     {
         struct minimal_symbol *msym;
-      ALL_OBJFILE_MSYMBOLS (objfile, msym)
-       {
-         if (SYMBOL_LINKAGE_NAME (msym)
-             && strcmp (SYMBOL_LINKAGE_NAME (msym), name) == 0)
-           {
+        msym = lookup_minimal_symbol (name, NULL, objfile);
+        if ( msym ) 
+         {
              *objfile_p = objfile;
              return msym;
-           }
-       }
+         }
     }

-- 
           Summary: Performance problem in find_minsym_and_objfile
           Product: gdb
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: symtab
        AssignedTo: unassigned at sourceware dot org
        ReportedBy: andre dot poenitz at nokia dot com
                CC: gdb-prs at sourceware dot org
 GCC build triplet: i486-linux-gnu
  GCC host triplet: i486-linux-gnu
GCC target triplet: i486-linux-gnu


http://sourceware.org/bugzilla/show_bug.cgi?id=11198

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