diff options
| author | Mark Wielaard <mark@klomp.org> | 2021-02-12 16:28:50 +0100 |
|---|---|---|
| committer | Mark Wielaard <mark@klomp.org> | 2021-02-17 16:52:57 +0100 |
| commit | ce6a126b01b2c8951dd941a95a92be71e34f2088 (patch) | |
| tree | c70be2b1a6c4ed23dbb8a5e65112a3a3b7d0208f /libdw | |
| parent | f146d5ec8e2eee566df6eb4c939cf29d779fc08c (diff) | |
| download | elfutils-ce6a126b01b2c8951dd941a95a92be71e34f2088.tar.gz | |
readelf, libdw: blocks aren't expressions for DWARF version 4
For DWARF version 4 or higher a block form really encodes a block,
not an expression location. Also constant offsets can be expressed
as DW_FORM_implicit_const in DWARF version 5.
Signed-off-by: Mark Wielaard <mark@klomp.org>
Diffstat (limited to 'libdw')
| -rw-r--r-- | libdw/ChangeLog | 6 | ||||
| -rw-r--r-- | libdw/dwarf_getlocation.c | 17 |
2 files changed, 23 insertions, 0 deletions
diff --git a/libdw/ChangeLog b/libdw/ChangeLog index b8038f00..f01bee39 100644 --- a/libdw/ChangeLog +++ b/libdw/ChangeLog @@ -1,3 +1,9 @@ +2021-02-12 Mark Wielaard <mark@klomp.org> + + * dwarf_getlocation.c (attr_ok): For DWARF version 4 or higher + block forms are not expression locations. + (is_constant_offset): DW_FORM_implicit_const is also a constant. + 2020-12-20 Dmitry V. Levin <ldv@altlinux.org> * .gitignore: New file. diff --git a/libdw/dwarf_getlocation.c b/libdw/dwarf_getlocation.c index 4e582db2..5db3cf97 100644 --- a/libdw/dwarf_getlocation.c +++ b/libdw/dwarf_getlocation.c @@ -48,6 +48,22 @@ attr_ok (Dwarf_Attribute *attr) if (dwarf_whatform (attr) == DW_FORM_exprloc) return true; + if (attr->cu->version >= 4) + { + /* Must be an exprloc (or constant), just not any block form. */ + switch (dwarf_whatform (attr)) + { + case DW_FORM_block: + case DW_FORM_block1: + case DW_FORM_block2: + case DW_FORM_block4: + __libdw_seterrno (DWARF_E_NO_LOC_VALUE); + return false; + default: + break; + } + } + /* Otherwise must be one of the attributes listed below. Older DWARF versions might have encoded the exprloc as block, and we cannot easily distinguish attributes in the loclist class because @@ -186,6 +202,7 @@ is_constant_offset (Dwarf_Attribute *attr, case DW_FORM_data8: case DW_FORM_sdata: case DW_FORM_udata: + case DW_FORM_implicit_const: break; } |