diff options
| author | Mark Wielaard <mark@klomp.org> | 2018-04-16 10:25:35 +0200 |
|---|---|---|
| committer | Mark Wielaard <mark@klomp.org> | 2018-04-16 10:25:35 +0200 |
| commit | 40b1f188a3b3194c7f62db9760d81f07db229b33 (patch) | |
| tree | 760b3ccef3c045871760408ab0a9d72b294ad75b /src | |
| parent | eaccd7870874d8a9821e298ceaabf492490b3fa7 (diff) | |
| download | elfutils-40b1f188a3b3194c7f62db9760d81f07db229b33.tar.gz | |
readelf: Fix advance_pc to use op_addr_advance, not just op_advance.
Found by John Mellor-Crummey.
The reason this bug wasn't found earlier is because gcc fixes
minimum_instr_len and max_ops_per_instr to 1 for all architectures
(in theory max_ops_per_instr could be overridden, but I didn't find
any architecture that does). And op_index always seems zero (it looks
like it is really only for special VLWI architectures).
So in all cases I saw it means that:
op_addr_advance = minimum_instr_len * ((op_index + op_advance)
/ max_ops_per_instr)
= 1 * ((0 + op_advance) / 1)
= op_advance
Completely masking the bug.
The libdw dwarf_getsrclines.c implementation does get this right.
Because it doesn't care about the data representation and so does
the calculation directly.
Signed-off-by: Mark Wielaard <mark@klomp.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/ChangeLog | 5 | ||||
| -rw-r--r-- | src/readelf.c | 2 |
2 files changed, 6 insertions, 1 deletions
diff --git a/src/ChangeLog b/src/ChangeLog index 068c87b9..2d525e6d 100644 --- a/src/ChangeLog +++ b/src/ChangeLog @@ -1,3 +1,8 @@ +2018-04-16 Mark Wielaard <mark@klomp.org> + + * readelf.c (print_debug_line_section). In advance_pc, advance + using op_addr_advance, not op_advance. + 2018-04-14 Mark Wielaard <mark@klomp.org> * readelf.c (attr_callback): Only show errors when not silent. diff --git a/src/readelf.c b/src/readelf.c index 8c0ef6ca..45fc8265 100644 --- a/src/readelf.c +++ b/src/readelf.c @@ -6971,7 +6971,7 @@ print_debug_line_section (Dwfl_Module *dwflmod, Ebl *ebl, GElf_Ehdr *ehdr, { op_addr_advance = minimum_instr_len * ((op_index + op_advance) / max_ops_per_instr); - address += op_advance; + address += op_addr_advance; show_op_index = (op_index > 0 || (op_index + op_advance) % max_ops_per_instr > 0); op_index = (op_index + op_advance) % max_ops_per_instr; |