gdb: restructure pretty printers into different files

This commit is contained in:
Robin Voetter 2022-03-16 18:13:10 +01:00
parent 0bd84e03b9
commit 4ff7553d6b
5 changed files with 370 additions and 391 deletions

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# pretty printing for stage1.
# put "source /path/to/stage1_gdb_pretty_printers.py" in ~/.gdbinit to load it automatically.
import gdb.printing
class ZigListPrinter:
def __init__(self, val):
self.val = val
def to_string(self):
return '%s of length %d, capacity %d' % (self.val.type.name, int(self.val['length']), int(self.val['capacity']))
def children(self):
def it(ziglist):
for i in range(int(ziglist.val['length'])):
item = ziglist.val['items'] + i
yield ('[%d]' % i, item.dereference())
return it(self)
def display_hint(self):
return 'array'
# handle both Buf and ZigList<char> because Buf* doesn't work otherwise (gdb bug?)
class BufPrinter:
def __init__(self, val):
self.val = val['list'] if val.type.name == 'Buf' else val
def to_string(self):
return self.val['items'].string(length=int(self.val['length']))
def display_hint(self):
return 'string'
pp = gdb.printing.RegexpCollectionPrettyPrinter('Zig stage1 compiler')
pp.add_printer('Buf', '^Buf$', BufPrinter)
pp.add_printer('ZigList<char>', '^ZigList<char>$', BufPrinter)
pp.add_printer('ZigList', '^ZigList<.*>$', ZigListPrinter)
gdb.printing.register_pretty_printer(gdb.current_objfile(), pp)

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# pretty printing for stage 2.
# put "source /path/to/stage2_gdb_pretty_printers.py" in ~/.gdbinit to load it automatically.
import re
import gdb.printing
class TypePrinter:
no_payload_count = 4096
# Keep in sync with src/type.zig
# Types which have no payload do not need to be entered here.
payload_type_names = {
'array_u8': 'type.Len',
'array_u8_sentinel_0': 'Len',
'single_const_pointer': 'ElemType',
'single_mut_pointer': 'ElemType',
'many_const_pointer': 'ElemType',
'many_mut_pointer': 'ElemType',
'c_const_pointer': 'ElemType',
'c_mut_pointer': 'ElemType',
'const_slice': 'ElemType',
'mut_slice': 'ElemType',
'optional': 'ElemType',
'optional_single_mut_pointer': 'ElemType',
'optional_single_const_pointer': 'ElemType',
'anyframe_T': 'ElemType',
'int_signed': 'Bits',
'int_unsigned': 'Bits',
'error_set': 'ErrorSet',
'error_set_inferred': 'ErrorSetInferred',
'error_set_merged': 'ErrorSetMerged',
'array': 'Array',
'vector': 'Array',
'array_sentinel': 'ArraySentinel',
'pointer': 'Pointer',
'function': 'Function',
'error_union': 'ErrorUnion',
'error_set_single': 'Name',
'opaque': 'Opaque',
'struct': 'Struct',
'union': 'Union',
'union_tagged': 'Union',
'enum_full, .enum_nonexhaustive': 'EnumFull',
'enum_simple': 'EnumSimple',
'enum_numbered': 'EnumNumbered',
'empty_struct': 'ContainerScope',
'tuple': 'Tuple',
'anon_struct': 'AnonStruct',
}
def __init__(self, val):
self.val = val
def tag(self):
tag_if_small_enough = self.val['tag_if_small_enough']
tag_type = tag_if_small_enough.type
if tag_if_small_enough < TypePrinter.no_payload_count:
return tag_if_small_enough
else:
return self.val['ptr_otherwise'].dereference()['tag']
def payload_type(self):
tag = self.tag()
if tag is None:
return None
type_name = TypePrinter.payload_type_names.get(str(tag))
if type_name is None:
return None
return gdb.lookup_type('struct type.%s' % type_name)
def to_string(self):
tag = self.tag()
if tag is None:
return '(invalid type)'
if self.val['tag_if_small_enough'] < TypePrinter.no_payload_count:
return '.%s' % str(tag)
return None
def children(self):
if self.val['tag_if_small_enough'] < TypePrinter.no_payload_count:
return
yield ('tag', '.%s' % str(self.tag()))
payload_type = self.payload_type()
if payload_type is not None:
yield ('payload', self.val['ptr_otherwise'].cast(payload_type.pointer()).dereference()['data'])
class ValuePrinter:
no_payload_count = 4096
# Keep in sync with src/value.zig
# Values which have no payload do not need to be entered here.
payload_type_names = {
'big_int_positive': 'BigInt',
'big_int_negative': 'BigInt',
'extern_fn': 'ExternFn',
'decl_ref': 'Decl',
'repeated': 'SubValue',
'eu_payload': 'SubValue',
'opt_payload': 'SubValue',
'empty_array_sentinel': 'SubValue',
'eu_payload_ptr': 'PayloadPtr',
'opt_payload_ptr': 'PayloadPtr',
'bytes': 'Bytes',
'enum_literal': 'Bytes',
'slice': 'Slice',
'enum_field_index': 'U32',
'ty': 'Ty',
'int_type': 'IntType',
'int_u64': 'U64',
'int_i64': 'I64',
'function': 'Function',
'variable': 'Variable',
'decl_ref_mut': 'DeclRefMut',
'elem_ptr': 'ElemPtr',
'field_ptr': 'FieldPtr',
'float_16': 'Float_16',
'float_32': 'Float_32',
'float_64': 'Float_64',
'float_80': 'Float_80',
'float_128': 'Float_128',
'error': 'Error',
'inferred_alloc': 'InferredAlloc',
'inferred_alloc_comptime': 'InferredAllocComptime',
'aggregate': 'Aggregate',
'union': 'Union',
'bound_fn': 'BoundFn',
}
def __init__(self, val):
self.val = val
def tag(self):
tag_if_small_enough = self.val['tag_if_small_enough']
tag_type = tag_if_small_enough.type
if tag_if_small_enough < ValuePrinter.no_payload_count:
return tag_if_small_enough
else:
return self.val['ptr_otherwise'].dereference()['tag']
def payload_type(self):
tag = self.tag()
if tag is None:
return None
type_name = ValuePrinter.payload_type_names.get(str(tag))
if type_name is None:
return None
return gdb.lookup_type('struct value.%s' % type_name)
def to_string(self):
tag = self.tag()
if tag is None:
return '(invalid value)'
if self.val['tag_if_small_enough'] < ValuePrinter.no_payload_count:
return '.%s' % str(tag)
return None
def children(self):
if self.val['tag_if_small_enough'] < ValuePrinter.no_payload_count:
return
yield ('tag', '.%s' % str(self.tag()))
payload_type = self.payload_type()
if payload_type is not None:
yield ('payload', self.val['ptr_otherwise'].cast(payload_type.pointer()).dereference()['data'])
pp = gdb.printing.RegexpCollectionPrettyPrinter('Zig stage2 compiler')
pp.add_printer('Type', r'^type\.Type$', TypePrinter)
pp.add_printer('Value', r'^value\.Value$', ValuePrinter)
gdb.printing.register_pretty_printer(gdb.current_objfile(), pp)

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# pretty printing for the standard library.
# put "source /path/to/stage2_gdb_pretty_printers.py" in ~/.gdbinit to load it automatically.
import re
import gdb.printing
# Handles both ArrayList and ArrayListUnmanaged.
class ArrayListPrinter:
def __init__(self, val):
self.val = val
def to_string(self):
type = self.val.type.name[len('std.array_list.'):]
type = re.sub(r'^ArrayListAligned(Unmanaged)?\((.*),null\)$', r'ArrayList\1(\2)', type)
return '%s of length %s, capacity %s' % (type, self.val['items']['len'], self.val['capacity'])
def children(self):
for i in range(self.val['items']['len']):
item = self.val['items']['ptr'] + i
yield ('[%d]' % i, item.dereference())
def display_hint(self):
return 'array'
class MultiArrayListPrinter:
def __init__(self, val):
self.val = val
def child_type(self):
(helper_fn, _) = gdb.lookup_symbol('%s.gdbHelper' % self.val.type.name)
return helper_fn.type.fields()[1].type.target()
def to_string(self):
type = self.val.type.name[len('std.multi_array_list.'):]
return '%s of length %s, capacity %s' % (type, self.val['len'], self.val['capacity'])
def slice(self):
fields = self.child_type().fields()
base = self.val['bytes']
cap = self.val['capacity']
len = self.val['len']
if len == 0:
return
fields = sorted(fields, key=lambda field: field.type.alignof, reverse=True)
for field in fields:
ptr = base.cast(field.type.pointer()).dereference().cast(field.type.array(len - 1))
base += field.type.sizeof * cap
yield (field.name, ptr)
def children(self):
for i, (name, ptr) in enumerate(self.slice()):
yield ('[%d]' % i, name)
yield ('[%d]' % i, ptr)
def display_hint(self):
return 'map'
# Handles both HashMap and HashMapUnmanaged.
class HashMapPrinter:
def __init__(self, val):
self.type = val.type
is_managed = re.search(r'^std\.hash_map\.HashMap\(', self.type.name)
self.val = val['unmanaged'] if is_managed else val
def header_ptr_type(self):
(helper_fn, _) = gdb.lookup_symbol('%s.gdbHelper' % self.val.type.name)
return helper_fn.type.fields()[1].type
def header(self):
if self.val['metadata'] == 0:
return None
return (self.val['metadata'].cast(self.header_ptr_type()) - 1).dereference()
def to_string(self):
type = self.type.name[len('std.hash_map.'):]
type = re.sub(r'^HashMap(Unmanaged)?\((.*),std.hash_map.AutoContext\(.*$', r'AutoHashMap\1(\2)', type)
hdr = self.header()
if hdr is not None:
cap = hdr['capacity']
else:
cap = 0
return '%s of length %s, capacity %s' % (type, self.val['size'], cap)
def children(self):
hdr = self.header()
if hdr is None:
return
is_map = self.display_hint() == 'map'
for i in range(hdr['capacity']):
metadata = self.val['metadata'] + i
if metadata.dereference()['used'] == 1:
yield ('[%d]' % i, (hdr['keys'] + i).dereference())
if is_map:
yield ('[%d]' % i, (hdr['values'] + i).dereference())
def display_hint(self):
for field in self.header_ptr_type().target().fields():
if field.name == 'values':
return 'map'
return 'array'
# Handles both ArrayHashMap and ArrayHashMapUnmanaged.
class ArrayHashMapPrinter:
def __init__(self, val):
self.type = val.type
is_managed = re.search(r'^std\.array_hash_map\.ArrayHashMap\(', self.type.name)
self.val = val['unmanaged'] if is_managed else val
def to_string(self):
type = self.type.name[len('std.array_hash_map.'):]
type = re.sub(r'^ArrayHashMap(Unmanaged)?\((.*),std.array_hash_map.AutoContext\(.*$', r'AutoArrayHashMap\1(\2)', type)
return '%s of length %s' % (type, self.val['entries']['len'])
def children(self):
entries = MultiArrayListPrinter(self.val['entries'])
len = self.val['entries']['len']
fields = {}
for name, ptr in entries.slice():
fields[str(name)] = ptr
for i in range(len):
if 'key' in fields:
yield ('[%d]' % i, fields['key'][i])
else:
yield ('[%d]' % i, '{}')
if 'value' in fields:
yield ('[%d]' % i, fields['value'][i])
def display_hint(self):
for name, ptr in MultiArrayListPrinter(self.val['entries']).slice():
if name == 'value':
return 'map'
return 'array'
pp = gdb.printing.RegexpCollectionPrettyPrinter('Zig standard library')
pp.add_printer('ArrayList', r'^std\.array_list\.ArrayListAligned(Unmanaged)?\(.*\)$', ArrayListPrinter)
pp.add_printer('MultiArrayList', r'^std\.multi_array_list\.MultiArrayList\(.*\)$', MultiArrayListPrinter)
pp.add_printer('HashMap', r'^std\.hash_map\.HashMap(Unmanaged)?\(.*\)$', HashMapPrinter)
pp.add_printer('ArrayHashMap', r'^std\.array_hash_map\.ArrayHashMap(Unmanaged)?\(.*\)$', ArrayHashMapPrinter)
gdb.printing.register_pretty_printer(gdb.current_objfile(), pp)

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# pretty printing for stage1, stage2 and the standard library
# put "source /path/to/zig-gdb.py" in ~/.gdbinit to load it automatically
import re
import gdb.printing
import gdb.types
class ZigListPrinter:
def __init__(self, val):
self.val = val
def to_string(self):
return '%s of length %d, capacity %d' % (self.val.type.name, int(self.val['length']), int(self.val['capacity']))
def children(self):
def it(ziglist):
for i in range(int(ziglist.val['length'])):
item = ziglist.val['items'] + i
yield ('[%d]' % i, item.dereference())
return it(self)
def display_hint(self):
return 'array'
# handle both Buf and ZigList<char> because Buf* doesn't work otherwise (gdb bug?)
class BufPrinter:
def __init__(self, val):
self.val = val['list'] if val.type.name == 'Buf' else val
def to_string(self):
return self.val['items'].string(length=int(self.val['length']))
def display_hint(self):
return 'string'
class SlicePrinter:
def __init__(self, val):
self.val = val
def children(self):
for i in range(self.val['len']):
yield ('[%d]' % i, (self.val['ptr'] + i).dereference())
def display_hint(self):
return 'array'
class SliceStringPrinter:
def __init__(self, val):
self.val = val
def to_string(self):
return self.val['ptr'].string(length=self.val['len'])
def display_hint(self):
return 'string'
# Handles both ArrayList and ArrayListUnmanaged.
class ArrayListPrinter:
def __init__(self, val):
self.val = val
def to_string(self):
type = self.val.type.name[len('std.array_list.'):]
type = re.sub(r'^ArrayListAligned(Unmanaged)?\((.*),null\)$', r'ArrayList\1(\2)', type)
return '%s of length %s, capacity %s' % (type, self.val['items']['len'], self.val['capacity'])
def children(self):
for i in range(self.val['items']['len']):
item = self.val['items']['ptr'] + i
yield ('[%d]' % i, item.dereference())
def display_hint(self):
return 'array'
class MultiArrayListPrinter:
def __init__(self, val):
self.val = val
def child_type(self):
(helper_fn, _) = gdb.lookup_symbol('%s.gdbHelper' % self.val.type.name)
return helper_fn.type.fields()[1].type.target()
def to_string(self):
type = self.val.type.name[len('std.multi_array_list.'):]
return '%s of length %s, capacity %s' % (type, self.val['len'], self.val['capacity'])
def slice(self):
fields = self.child_type().fields()
base = self.val['bytes']
cap = self.val['capacity']
len = self.val['len']
if len == 0:
return
fields = sorted(fields, key=lambda field: field.type.alignof, reverse=True)
for field in fields:
ptr = base.cast(field.type.pointer()).dereference().cast(field.type.array(len - 1))
base += field.type.sizeof * cap
yield (field.name, ptr)
def children(self):
for i, (name, ptr) in enumerate(self.slice()):
yield ('[%d]' % i, name)
yield ('[%d]' % i, ptr)
def display_hint(self):
return 'map'
# Handles both HashMap and HashMapUnmanaged.
class HashMapPrinter:
def __init__(self, val):
self.type = val.type
is_managed = re.search(r'^std\.hash_map\.HashMap\(', self.type.name)
self.val = val['unmanaged'] if is_managed else val
def header_ptr_type(self):
(helper_fn, _) = gdb.lookup_symbol('%s.gdbHelper' % self.val.type.name)
return helper_fn.type.fields()[1].type
def header(self):
if self.val['metadata'] == 0:
return None
return (self.val['metadata'].cast(self.header_ptr_type()) - 1).dereference()
def to_string(self):
type = self.type.name[len('std.hash_map.'):]
type = re.sub(r'^HashMap(Unmanaged)?\((.*),std.hash_map.AutoContext\(.*$', r'AutoHashMap\1(\2)', type)
hdr = self.header()
if hdr is not None:
cap = hdr['capacity']
else:
cap = 0
return '%s of length %s, capacity %s' % (type, self.val['size'], cap)
def children(self):
hdr = self.header()
if hdr is None:
return
is_map = self.display_hint() == 'map'
for i in range(hdr['capacity']):
metadata = self.val['metadata'] + i
if metadata.dereference()['used'] == 1:
yield ('[%d]' % i, (hdr['keys'] + i).dereference())
if is_map:
yield ('[%d]' % i, (hdr['values'] + i).dereference())
def display_hint(self):
for field in self.header_ptr_type().target().fields():
if field.name == 'values':
return 'map'
return 'array'
# Handles both ArrayHashMap and ArrayHashMapUnmanaged.
class ArrayHashMapPrinter:
def __init__(self, val):
self.type = val.type
is_managed = re.search(r'^std\.array_hash_map\.ArrayHashMap\(', self.type.name)
self.val = val['unmanaged'] if is_managed else val
def to_string(self):
type = self.type.name[len('std.array_hash_map.'):]
type = re.sub(r'^ArrayHashMap(Unmanaged)?\((.*),std.array_hash_map.AutoContext\(.*$', r'AutoArrayHashMap\1(\2)', type)
return '%s of length %s' % (type, self.val['entries']['len'])
def children(self):
entries = MultiArrayListPrinter(self.val['entries'])
len = self.val['entries']['len']
fields = {}
for name, ptr in entries.slice():
fields[str(name)] = ptr
for i in range(len):
if 'key' in fields:
yield ('[%d]' % i, fields['key'][i])
else:
yield ('[%d]' % i, '{}')
if 'value' in fields:
yield ('[%d]' % i, fields['value'][i])
def display_hint(self):
for name, ptr in MultiArrayListPrinter(self.val['entries']).slice():
if name == 'value':
return 'map'
return 'array'
class TypePrinter:
no_payload_count = 4096
# Keep in sync with src/type.zig
# Types which have no payload do not need to be entered here.
payload_type_names = {
'array_u8': 'type.Len',
'array_u8_sentinel_0': 'Len',
'single_const_pointer': 'ElemType',
'single_mut_pointer': 'ElemType',
'many_const_pointer': 'ElemType',
'many_mut_pointer': 'ElemType',
'c_const_pointer': 'ElemType',
'c_mut_pointer': 'ElemType',
'const_slice': 'ElemType',
'mut_slice': 'ElemType',
'optional': 'ElemType',
'optional_single_mut_pointer': 'ElemType',
'optional_single_const_pointer': 'ElemType',
'anyframe_T': 'ElemType',
'int_signed': 'Bits',
'int_unsigned': 'Bits',
'error_set': 'ErrorSet',
'error_set_inferred': 'ErrorSetInferred',
'error_set_merged': 'ErrorSetMerged',
'array': 'Array',
'vector': 'Array',
'array_sentinel': 'ArraySentinel',
'pointer': 'Pointer',
'function': 'Function',
'error_union': 'ErrorUnion',
'error_set_single': 'Name',
'opaque': 'Opaque',
'struct': 'Struct',
'union': 'Union',
'union_tagged': 'Union',
'enum_full, .enum_nonexhaustive': 'EnumFull',
'enum_simple': 'EnumSimple',
'enum_numbered': 'EnumNumbered',
'empty_struct': 'ContainerScope',
'tuple': 'Tuple',
'anon_struct': 'AnonStruct',
}
def __init__(self, val):
self.val = val
def tag(self):
tag_if_small_enough = self.val['tag_if_small_enough']
tag_type = tag_if_small_enough.type
if tag_if_small_enough < TypePrinter.no_payload_count:
return tag_if_small_enough
else:
return self.val['ptr_otherwise'].dereference()['tag']
def payload_type(self):
tag = self.tag()
if tag is None:
return None
type_name = TypePrinter.payload_type_names.get(str(tag))
if type_name is None:
return None
return gdb.lookup_type('struct type.%s' % type_name)
def to_string(self):
tag = self.tag()
if tag is None:
return '(invalid type)'
if self.val['tag_if_small_enough'] < TypePrinter.no_payload_count:
return '.%s' % str(tag)
return None
def children(self):
if self.val['tag_if_small_enough'] < TypePrinter.no_payload_count:
return
yield ('tag', '.%s' % str(self.tag()))
payload_type = self.payload_type()
if payload_type is not None:
yield ('payload', self.val['ptr_otherwise'].cast(payload_type.pointer()).dereference()['data'])
class ValuePrinter:
no_payload_count = 4096
# Keep in sync with src/value.zig
# Values which have no payload do not need to be entered here.
payload_type_names = {
'big_int_positive': 'BigInt',
'big_int_negative': 'BigInt',
'extern_fn': 'ExternFn',
'decl_ref': 'Decl',
'repeated': 'SubValue',
'eu_payload': 'SubValue',
'opt_payload': 'SubValue',
'empty_array_sentinel': 'SubValue',
'eu_payload_ptr': 'PayloadPtr',
'opt_payload_ptr': 'PayloadPtr',
'bytes': 'Bytes',
'enum_literal': 'Bytes',
'slice': 'Slice',
'enum_field_index': 'U32',
'ty': 'Ty',
'int_type': 'IntType',
'int_u64': 'U64',
'int_i64': 'I64',
'function': 'Function',
'variable': 'Variable',
'decl_ref_mut': 'DeclRefMut',
'elem_ptr': 'ElemPtr',
'field_ptr': 'FieldPtr',
'float_16': 'Float_16',
'float_32': 'Float_32',
'float_64': 'Float_64',
'float_80': 'Float_80',
'float_128': 'Float_128',
'error': 'Error',
'inferred_alloc': 'InferredAlloc',
'inferred_alloc_comptime': 'InferredAllocComptime',
'aggregate': 'Aggregate',
'union': 'Union',
'bound_fn': 'BoundFn',
}
def __init__(self, val):
self.val = val
def tag(self):
tag_if_small_enough = self.val['tag_if_small_enough']
tag_type = tag_if_small_enough.type
if tag_if_small_enough < ValuePrinter.no_payload_count:
return tag_if_small_enough
else:
return self.val['ptr_otherwise'].dereference()['tag']
def payload_type(self):
tag = self.tag()
if tag is None:
return None
type_name = ValuePrinter.payload_type_names.get(str(tag))
if type_name is None:
return None
return gdb.lookup_type('struct value.%s' % type_name)
def to_string(self):
tag = self.tag()
if tag is None:
return '(invalid value)'
if self.val['tag_if_small_enough'] < ValuePrinter.no_payload_count:
return '.%s' % str(tag)
return None
def children(self):
if self.val['tag_if_small_enough'] < ValuePrinter.no_payload_count:
return
yield ('tag', '.%s' % str(self.tag()))
payload_type = self.payload_type()
if payload_type is not None:
yield ('payload', self.val['ptr_otherwise'].cast(payload_type.pointer()).dereference()['data'])
pp1 = gdb.printing.RegexpCollectionPrettyPrinter('Zig stage1 compiler')
pp1.add_printer('Buf', '^Buf$', BufPrinter)
pp1.add_printer('ZigList<char>', '^ZigList<char>$', BufPrinter)
pp1.add_printer('ZigList', '^ZigList<.*>$', ZigListPrinter)
gdb.printing.register_pretty_printer(gdb.current_objfile(), pp1)
pplang = gdb.printing.RegexpCollectionPrettyPrinter('Zig language')
pplang.add_printer('Slice', '^\[\]u8', SliceStringPrinter)
pplang.add_printer('Slice', '^\[\]', SlicePrinter)
gdb.printing.register_pretty_printer(gdb.current_objfile(), pplang)
ppstd = gdb.printing.RegexpCollectionPrettyPrinter('Zig standard library')
ppstd.add_printer('ArrayList', r'^std\.array_list\.ArrayListAligned(Unmanaged)?\(.*\)$', ArrayListPrinter)
ppstd.add_printer('MultiArrayList', r'^std\.multi_array_list\.MultiArrayList\(.*\)$', MultiArrayListPrinter)
ppstd.add_printer('HashMap', r'^std\.hash_map\.HashMap(Unmanaged)?\(.*\)$', HashMapPrinter)
ppstd.add_printer('ArrayHashMap', r'^std\.array_hash_map\.ArrayHashMap(Unmanaged)?\(.*\)$', ArrayHashMapPrinter)
gdb.printing.register_pretty_printer(gdb.current_objfile(), ppstd)
pp2 = gdb.printing.RegexpCollectionPrettyPrinter('Zig stage2 compiler')
pp2.add_printer('Type', r'^type\.Type$', TypePrinter)
pp2.add_printer('Value', r'^value\.Value$', ValuePrinter)
gdb.printing.register_pretty_printer(gdb.current_objfile(), pp2)

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@ -1,5 +1,5 @@
# gdb pretty printers for Zig language constructs
# pretty printing for the language.
# put "source /path/to/zig_gdb_pretty_printers.py" in ~/.gdbinit to load it automatically.
import gdb.printing
class ZigPrettyPrinter(gdb.printing.PrettyPrinter):