Hi,
vec.h has this method:
template<typename T, typename A>
inline T *
vec_safe_push (vec<T, A, vl_embed> *&v, const T &obj CXX_MEM_STAT_INFO)
where v is a reference to a pointer to vec. This matches the regex for
VecPrinter, so gdbhooks.py attempts to print it but chokes on the reference.
I see the following:
#1 0x0000000002b84b7b in vec_safe_push<edge_def*, va_gc> (v=Traceback (most
recent call last):
File "$SRC/gcc/gcc/gdbhooks.py", line 486, in to_string
return '0x%x' % intptr(self.gdbval)
File "$SRC/gcc/gcc/gdbhooks.py", line 168, in intptr
return long(gdbval) if sys.version_info.major == 2 else int(gdbval)
gdb.error: Cannot convert value to long.
This patch makes VecPrinter handle such references by stripping them
(dereferencing) at the top of the relevant functions.
I thought about trying to make VecPrinter.{to_string,children} robust
against non-pointer values (i.e. actual vec structs) as the current
calls to intptr will fail on those. However, I then realised that the
current regex only matches pointer types:
pp.add_printer_for_regex(r'vec<(\S+), (\S+), (\S+)> \*',
'vec',
VecPrinter)
That is somewhat at odds with the (pre-existing) code in
VecPrinter.children which appears to attempt to handle non-pointer
types. ISTM either we should drop the handling for non-pointer types
(since the regex requires a pointer) or (perhaps more usefully) relax
the regex to allow matching a plain vec<...> struct and fix the member
functions to handle those properly.
Any thoughts on that, Dave? Is the current patch OK as an intermediate
step (manually tested by verifying both a vec*& and vec* print OK)?
Thanks,
Alex
gcc/ChangeLog:
* gdbhooks.py (strip_ref): New. Use it ...
(VecPrinter.to_string): ... here,
(VecPrinter.children): ... and here.
diff --git a/gcc/gdbhooks.py b/gcc/gdbhooks.py
index 904ee28423a..a91e5fd2a83 100644
--- a/gcc/gdbhooks.py
+++ b/gcc/gdbhooks.py
@@ -472,6 +472,11 @@ def get_vec_kind(val):
else:
assert False, f"unexpected vec kind {kind}"
+def strip_ref(gdbval):
+ if gdbval.type.code == gdb.TYPE_CODE_REF:
+ return gdbval.referenced_value ()
+ return gdbval
+
class VecPrinter:
# -ex "up" -ex "p bb->preds"
def __init__(self, gdbval):
@@ -483,10 +488,10 @@ class VecPrinter:
def to_string (self):
# A trivial implementation; prettyprinting the contents is done
# by gdb calling the "children" method below.
- return '0x%x' % intptr(self.gdbval)
+ return '0x%x' % intptr(strip_ref(self.gdbval))
def children (self):
- val = self.gdbval
+ val = strip_ref(self.gdbval)
if intptr(val) != 0 and get_vec_kind(val) == VEC_KIND_PTR:
val = val['m_vec']
