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Joel Brobecker 0c92d8c1c3 DWARF frame unwinder executes one too many rows
The problem is trying to unwind from a function where %ebp is NOT
used as the frame pointer, and the size of the frame changes over
the lifetime of that function.

For instance, trying to unwind past the GNAT runtime function
called system.tasking.rendezvous.timed_selective_wait on x86-linux,
one can get:

    (gdb) bt
    [...]
    #3  0x0805364b in system.tasking.rendezvous.timed_selective_wait ()
    #4  0xb7fe5068 in ?? ()
    Backtrace stopped: previous frame inner to this frame (corrupt stack?)

Looking at the CFI, we find the following initial instructions...

>   DW_CFA_def_cfa: %esp+4 (r4 ofs 4)
>   DW_CFA_offset: %eip at cfa-4  (r8 = %eip)

... and the associated FDE:

> 00001be4 00000054 00001be8 FDE cie=00000000 pc=08053310..08053951
[...]
>   DW_CFA_advance_loc: 8 to 080534ad
>   DW_CFA_def_cfa_offset: 112
>   DW_CFA_advance_loc2: 414 to 0805364b
>   DW_CFA_def_cfa_offset: 108
[...]

The problem is that the DWARF frame unwinder executed the FDE until
the row for PC == 0x0805364b. But in reality, our program hasn't
executed the instruction at that address yet (it is the return address).
So GDB executed a little too much of the FDE, giving us the wrong
offset for the frame base, and thus the wrong address where %eip
got saved.

This patch fixes the problem by using a more correct PC as the bound
for executing the FDE.

gdb/ChangeLog:

        * dwarf2-frame.c (dwarf2_frame_cache): Use
        get_frame_address_in_block instead of get_frame_pc as
        the bound for executing the frame's FDE.

gdb/testsuite/ChangeLog:

        * gdb.ada/rdv_wait: New testcase.
2012-08-16 15:45:46 +00:00
bfd PR binutils/14475: 2012-08-16 14:24:44 +00:00
binutils Add support for 64-bit ARM architecture: AArch64 2012-08-13 14:52:54 +00:00
config
cpu
elfcpp elfcpp/ 2012-08-14 02:22:32 +00:00
etc
gas opcodes/ 2012-08-15 21:25:21 +00:00
gdb DWARF frame unwinder executes one too many rows 2012-08-16 15:45:46 +00:00
gold * x86_64.cc (Target_x86_64::Scan::global): Fix erroneous call to 2012-08-15 04:03:54 +00:00
gprof Updated Vietnamese translation. 2012-08-09 14:46:44 +00:00
include Add support for 64-bit ARM architecture: AArch64 2012-08-13 14:52:54 +00:00
intl
ld oops - accidentally omitted from previous delta 2012-08-14 12:10:12 +00:00
libdecnumber
libiberty
opcodes * rl78-decode.opc (rl78_decode_opcode): Merge %e and %[01] 2012-08-15 22:37:56 +00:00
readline
sim oops - acxidentally omitted from previous delta. 2012-08-16 08:38:45 +00:00
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		   README for GNU development tools

This directory contains various GNU compilers, assemblers, linkers, 
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If you are receiving this as part of a GDB release, see the file gdb/README.
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	CC=gcc ./configure
	make

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	setenv CC gcc
	./configure
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