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Date: Sun, 07 Feb 2010 14:32:00 -0000
Subject: [Bug c/42993]  New: simplify-rtx.c:244: Conditional jump or move depends on uninitialised value(s)
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From: "dcb314 at hotmail dot com" <gcc-bugzilla@gcc.gnu.org>
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I just tried to compile the Linux kernel 2.6.33-rc6 under valgrind
with the C compiler version 4.5 snapshot 20100128 and valgrind said

==2968== Conditional jump or move depends on uninitialised value(s)
==2968==    at 0x7A6925: delegitimize_mem_from_attrs (simplify-rtx.c:244)
==2968==    by 0x961517: ix86_delegitimize_address (i386.c:10883)
==2968==    by 0x93E5F6: emit_note_insn_var_location (var-tracking.c:6515)
==2968==    by 0xCB84D7: htab_traverse_noresize (hashtab.c:753)
==2968==    by 0x941376: emit_notes_for_changes (var-tracking.c:6741)
==2968==    by 0x946A67: vt_emit_notes (var-tracking.c:7106)
==2968==    by 0x94A602: variable_tracking_main (var-tracking.c:7637)
==2968==    by 0x722ECA: execute_one_pass (passes.c:1561)
==2968==    by 0x723154: execute_pass_list (passes.c:1616)
==2968==    by 0x723166: execute_pass_list (passes.c:1617)
==2968==    by 0x723166: execute_pass_list (passes.c:1617)
==2968==    by 0x818C94: tree_rest_of_compilation (tree-optimize.c:413)
==2968==

Line 244 of simplify-rtx.c is

            if (bitsize != GET_MODE_BITSIZE (mode)
                || (bitpos % BITS_PER_UNIT)
                || (toffset && !host_integerp (toffset, 0)))
              decl = NULL;

Preprocessed source code attached. Flags -Os -g required.


-- 
           Summary: simplify-rtx.c:244: Conditional jump or move depends on
                    uninitialised value(s)
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dcb314 at hotmail dot com
  GCC host triplet: x86_64-suse-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42993