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author | Pedro Alves <palves@redhat.com> | 2015-11-28 16:39:31 +0000 |
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committer | Pedro Alves <palves@redhat.com> | 2015-11-28 16:39:31 +0000 |
commit | c4be264168ee2f6c38b6b9b3db0a166441be478b (patch) | |
tree | 28cf578bbf06b022e4dcefda28a0e831270184f1 /libiberty/ChangeLog | |
parent | f3363926de602b7590526740a01a64ca973ca78a (diff) | |
download | gdb-c4be264168ee2f6c38b6b9b3db0a166441be478b.zip gdb-c4be264168ee2f6c38b6b9b3db0a166441be478b.tar.gz gdb-c4be264168ee2f6c38b6b9b3db0a166441be478b.tar.bz2 |
PR other/61321 - demangler crash on casts in template parameters
The fix for bug 59195:
[C++ demangler handles conversion operator incorrectly]
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59195
unfortunately makes the demangler crash due to infinite recursion, in
case of casts in template parameters.
For example, with:
template<int> struct A {};
template <typename Y> void function_temp(A<sizeof ((Y)(999))>) {}
template void function_temp<int>(A<sizeof (int)>);
The 'function_temp<int>' instantiation above mangles to:
_Z13function_tempIiEv1AIXszcvT_Li999EEE
The demangler parses this as:
typed name
template
name 'function_temp'
template argument list
builtin type int
function type
builtin type void
argument list
template (*)
name 'A'
template argument list
unary operator
operator sizeof
unary operator
cast
template parameter 0 (**)
literal
builtin type int
name '999'
And after the fix for 59195, due to:
static void
d_print_cast (struct d_print_info *dpi, int options,
const struct demangle_component *dc)
{
...
/* For a cast operator, we need the template parameters from
the enclosing template in scope for processing the type. */
if (dpi->current_template != NULL)
{
dpt.next = dpi->templates;
dpi->templates = &dpt;
dpt.template_decl = dpi->current_template;
}
when printing the template argument list of A (what should be "<sizeof
(int)>"), the template parameter 0 (that is, "T_", the '**' above) now
refers to the first parameter of the the template argument list of the
'A' template (the '*' above), exactly what we were already trying to
print. This leads to infinite recursion, and stack exaustion. The
template parameter 0 should actually refer to the first parameter of
the 'function_temp' template.
Where it reads "for the cast operator" in the comment in d_print_cast
(above), it's really talking about a conversion operator, like:
struct A { template <typename U> explicit operator U(); };
We don't want to inject the template parameters from the enclosing
template in scope when processing a cast _expression_, only when
handling a conversion operator.
The problem is that DEMANGLE_COMPONENT_CAST is currently ambiguous,
and means _both_ 'conversion operator' and 'cast expression'.
Fix this by adding a new DEMANGLE_COMPONENT_CONVERSION component type,
which does what DEMANGLE_COMPONENT_CAST does today, and making
DEMANGLE_COMPONENT_CAST just simply print its component subtree.
I think we could instead reuse DEMANGLE_COMPONENT_CAST and in
d_print_comp_inner still do:
@@ -5001,9 +5013,9 @@ d_print_comp_inner (struct d_print_info *dpi, int options,
d_print_comp (dpi, options, dc->u.s_extended_operator.name);
return;
case DEMANGLE_COMPONENT_CAST:
d_append_string (dpi, "operator ");
- d_print_cast (dpi, options, dc);
+ d_print_conversion (dpi, options, dc);
return;
leaving the unary cast case below calling d_print_cast, but seems to
me that spliting the component types makes it easier to reason about
the code.
g++'s testsuite actually generates three symbols that crash the
demangler in the same way. I've added those as tests in the demangler
testsuite as well.
And then this fixes PR other/61233 too, which happens to be a
demangler crash originally reported to GDB, at:
https://sourceware.org/bugzilla/show_bug.cgi?id=16957
Bootstrapped and regtested on x86_64 Fedora 20.
Also ran this through GDB's testsuite. GDB will require a small
update to use DEMANGLE_COMPONENT_CONVERSION in one place it's using
DEMANGLE_COMPONENT_CAST in its sources.
libiberty/
2015-11-27 Pedro Alves <palves@redhat.com>
PR other/61321
PR other/61233
* demangle.h (enum demangle_component_type)
<DEMANGLE_COMPONENT_CONVERSION>: New value.
* cp-demangle.c (d_demangle_callback, d_make_comp): Handle
DEMANGLE_COMPONENT_CONVERSION.
(is_ctor_dtor_or_conversion): Handle DEMANGLE_COMPONENT_CONVERSION
instead of DEMANGLE_COMPONENT_CAST.
(d_operator_name): Return a DEMANGLE_COMPONENT_CONVERSION
component if handling a conversion.
(d_count_templates_scopes, d_print_comp_inner): Handle
DEMANGLE_COMPONENT_CONVERSION.
(d_print_comp_inner): Handle DEMANGLE_COMPONENT_CONVERSION instead
of DEMANGLE_COMPONENT_CAST.
(d_print_cast): Rename as ...
(d_print_conversion): ... this. Adjust comments.
(d_print_cast): Rewrite - simply print the left subcomponent.
* cp-demint.c (cplus_demangle_fill_component): Handle
DEMANGLE_COMPONENT_CONVERSION.
* testsuite/demangle-expected: Add tests.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@231020 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'libiberty/ChangeLog')
-rw-r--r-- | libiberty/ChangeLog | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog index 5d672a8..3d2ff59 100644 --- a/libiberty/ChangeLog +++ b/libiberty/ChangeLog @@ -1,3 +1,27 @@ +2015-11-27 Pedro Alves <palves@redhat.com> + + PR other/61321 + PR other/61233 + * demangle.h (enum demangle_component_type) + <DEMANGLE_COMPONENT_CONVERSION>: New value. + * cp-demangle.c (d_demangle_callback, d_make_comp): Handle + DEMANGLE_COMPONENT_CONVERSION. + (is_ctor_dtor_or_conversion): Handle DEMANGLE_COMPONENT_CONVERSION + instead of DEMANGLE_COMPONENT_CAST. + (d_operator_name): Return a DEMANGLE_COMPONENT_CONVERSION + component if handling a conversion. + (d_count_templates_scopes, d_print_comp_inner): Handle + DEMANGLE_COMPONENT_CONVERSION. + (d_print_comp_inner): Handle DEMANGLE_COMPONENT_CONVERSION instead + of DEMANGLE_COMPONENT_CAST. + (d_print_cast): Rename as ... + (d_print_conversion): ... this. Adjust comments. + (d_print_cast): Rewrite - simply print the left subcomponent. + * cp-demint.c (cplus_demangle_fill_component): Handle + DEMANGLE_COMPONENT_CONVERSION. + + * testsuite/demangle-expected: Add tests. + 2015-11-12 Mike Stump <mikestump@comcast.net> * Makefile.in (etags tags TAGS): Use && instead of ;. |