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* [PATCH] Fix gdb FilteringTypePrinter (again)
@ 2022-10-06 17:38 François Dumont
  2022-11-14 17:57 ` François Dumont
  2022-11-15 16:17 ` Jonathan Wakely
  0 siblings, 2 replies; 8+ messages in thread
From: François Dumont @ 2022-10-06 17:38 UTC (permalink / raw)
  To: libstdc++; +Cc: gcc-patches

[-- Attachment #1: Type: text/plain, Size: 1938 bytes --]

Hi

Looks like the previous patch was not enough. When using it in the 
context of a build without dual abi and versioned namespace I started 
having failures again. I guess I hadn't rebuild everything properly.

This time I think the problem was in those lines:

             if self.type_obj == type_obj:
                 return strip_inline_namespaces(self.name)

I've added a call to gdb.types.get_basic_type so that we do not compare 
a type with its typedef.

Thanks for the pointer to the doc !

Doing so I eventually use your code Jonathan to make FilteringTypeFilter 
more specific to a given instantiation.

     libstdc++: Fix gdb FilteringTypePrinter

     Once we found a matching FilteringTypePrinter instance we look for 
the associated
     typedef and check that the returned Python Type is equal to the 
Type to recognize.
     But gdb Python Type includes properties to distinguish a typedef 
from the actual
     type. So use gdb.types.get_basic_type to check if we are indeed on 
the same type.

     Additionnaly enhance FilteringTypePrinter matching mecanism by 
introducing targ1 that,
     if not None, will be used as the 1st template parameter.

     libstdc++-v3/ChangeLog:

             * python/libstdcxx/v6/printers.py (FilteringTypePrinter): 
Rename 'match' field
             'template'. Add self.targ1 to specify the first template 
parameter of the instantiation
             to match.
             (add_one_type_printer): Add targ1 optional parameter, 
default to None.
             Use gdb.types.get_basic_type to compare the type to 
recognize and the type
             returned from the typedef lookup.
             (register_type_printers): Adapt calls to add_one_type_printers.

Tested under Linux x86_64 normal, version namespace with or without dual 
abi.

François


[-- Attachment #2: gdb_printers.patch --]
[-- Type: text/x-patch, Size: 8406 bytes --]

diff --git a/libstdc++-v3/python/libstdcxx/v6/printers.py b/libstdc++-v3/python/libstdcxx/v6/printers.py
index 0fa7805183e..52339b247d8 100644
--- a/libstdc++-v3/python/libstdcxx/v6/printers.py
+++ b/libstdc++-v3/python/libstdcxx/v6/printers.py
@@ -2040,62 +2040,72 @@ def add_one_template_type_printer(obj, name, defargs):
 
 class FilteringTypePrinter(object):
     r"""
-    A type printer that uses typedef names for common template specializations.
+    A type printer that uses typedef names for common template instantiations.
 
     Args:
-        match (str): The class template to recognize.
+        template (str): The class template to recognize.
         name (str): The typedef-name that will be used instead.
+        targ1 (str): The first template argument.
+            If arg1 is provided (not None), only template instantiations with this type
+            as the first template argument, e.g. if template='basic_string<targ1'
 
-    Checks if a specialization of the class template 'match' is the same type
+    Checks if an instantiation of the class template 'template' is the same type
     as the typedef 'name', and prints it as 'name' instead.
 
-    e.g. if an instantiation of std::basic_istream<C, T> is the same type as
+    e.g. for template='basic_istream', name='istream', if any instantiation of
+    std::basic_istream<C, T> is the same type as std::istream then print it as
+    std::istream.
+
+    e.g. for template='basic_istream', name='istream', targ1='char', if any
+    instantiation of std::basic_istream<char, T> is the same type as
     std::istream then print it as std::istream.
     """
 
-    def __init__(self, match, name):
-        self.match = match
+    def __init__(self, template, name, targ1):
+        self.template = template
         self.name = name
+        self.targ1 = targ1
         self.enabled = True
 
     class _recognizer(object):
         "The recognizer class for FilteringTypePrinter."
 
-        def __init__(self, match, name):
-            self.match = match
+        def __init__(self, template, name, targ1):
+            self.template = template
             self.name = name
+            self.targ1 = targ1
             self.type_obj = None
 
         def recognize(self, type_obj):
             """
-            If type_obj starts with self.match and is the same type as
+            If type_obj starts with self.template and is the same type as
             self.name then return self.name, otherwise None.
             """
             if type_obj.tag is None:
                 return None
 
             if self.type_obj is None:
-                if not type_obj.tag.startswith(self.match):
+                if self.targ1 is not None:
+                    if not type_obj.tag.startswith('{}<{}'.format(self.template, self.targ1)):
+                        # Filter didn't match.
+                        return None
+                elif not type_obj.tag.startswith(self.template):
                     # Filter didn't match.
                     return None
+
                 try:
                     self.type_obj = gdb.lookup_type(self.name).strip_typedefs()
                 except:
                     pass
-            if self.type_obj == type_obj:
-                return strip_inline_namespaces(self.name)
 
             if self.type_obj is None:
                 return None
 
-            # Workaround ambiguous typedefs matching both std:: and std::__cxx11:: symbols.
-            ambiguous = False
-            for ch in ('', 'w', 'u8', 'u16', 'u32'):
-                if self.name == 'std::' + ch + 'string':
-                    ambiguous = True
-                    break
+            if gdb.types.get_basic_type(self.type_obj) == gdb.types.get_basic_type(type_obj):
+                return strip_inline_namespaces(self.name)
 
-            if ambiguous:
+            # Workaround ambiguous typedefs matching both std:: and std::__cxx11:: symbols.
+            if self.template.split('::')[-1] == 'basic_string':
                 if self.type_obj.tag.replace('__cxx11::', '') == type_obj.tag.replace('__cxx11::', ''):
                     return strip_inline_namespaces(self.name)
 
@@ -2103,14 +2113,14 @@ class FilteringTypePrinter(object):
 
     def instantiate(self):
         "Return a recognizer object for this type printer."
-        return self._recognizer(self.match, self.name)
+        return self._recognizer(self.template, self.name, self.targ1)
 
-def add_one_type_printer(obj, match, name):
-    printer = FilteringTypePrinter('std::' + match, 'std::' + name)
+def add_one_type_printer(obj, template, name, targ1 = None):
+    printer = FilteringTypePrinter('std::' + template, 'std::' + name, targ1)
     gdb.types.register_type_printer(obj, printer)
-    if _versioned_namespace and not '__cxx11' in match:
+    if _versioned_namespace and not '__cxx11' in template:
         ns = 'std::' + _versioned_namespace
-        printer = FilteringTypePrinter(ns + match, ns + name)
+        printer = FilteringTypePrinter(ns + template, ns + name, targ1)
         gdb.types.register_type_printer(obj, printer)
 
 def register_type_printers(obj):
@@ -2120,29 +2130,33 @@ def register_type_printers(obj):
         return
 
     # Add type printers for typedefs std::string, std::wstring etc.
-    for ch in ('', 'w', 'u8', 'u16', 'u32'):
-        add_one_type_printer(obj, 'basic_string', ch + 'string')
-        add_one_type_printer(obj, '__cxx11::basic_string', ch + 'string')
+    for ch in (('', 'char'),
+               ('w', 'wchar_t'),
+               ('u8', 'char8_t'),
+               ('u16', 'char16_t'),
+               ('u32', 'char32_t')):
+        add_one_type_printer(obj, 'basic_string', ch[0] + 'string', ch[1])
+        add_one_type_printer(obj, '__cxx11::basic_string', ch[0] + 'string', ch[1])
         # Typedefs for __cxx11::basic_string used to be in namespace __cxx11:
         add_one_type_printer(obj, '__cxx11::basic_string',
-                             '__cxx11::' + ch + 'string')
-        add_one_type_printer(obj, 'basic_string_view', ch + 'string_view')
+                             '__cxx11::' + ch[0] + 'string', ch[1])
+        add_one_type_printer(obj, 'basic_string_view', ch[0] + 'string_view', ch[1])
 
     # Add type printers for typedefs std::istream, std::wistream etc.
-    for ch in ('', 'w'):
+    for ch in (('', 'char'), ('w', 'wchar_t')):
         for x in ('ios', 'streambuf', 'istream', 'ostream', 'iostream',
                   'filebuf', 'ifstream', 'ofstream', 'fstream'):
-            add_one_type_printer(obj, 'basic_' + x, ch + x)
+            add_one_type_printer(obj, 'basic_' + x, ch[0] + x, ch[1])
         for x in ('stringbuf', 'istringstream', 'ostringstream',
                   'stringstream'):
-            add_one_type_printer(obj, 'basic_' + x, ch + x)
+            add_one_type_printer(obj, 'basic_' + x, ch[0] + x, ch[1])
             # <sstream> types are in __cxx11 namespace, but typedefs aren't:
-            add_one_type_printer(obj, '__cxx11::basic_' + x, ch + x)
+            add_one_type_printer(obj, '__cxx11::basic_' + x, ch[0] + x, ch[1])
 
     # Add type printers for typedefs regex, wregex, cmatch, wcmatch etc.
     for abi in ('', '__cxx11::'):
-        for ch in ('', 'w'):
-            add_one_type_printer(obj, abi + 'basic_regex', abi + ch + 'regex')
+        for ch in (('', 'char'), ('w', 'wchar_t')):
+            add_one_type_printer(obj, abi + 'basic_regex', abi + ch[0] + 'regex', ch[1])
         for ch in ('c', 's', 'wc', 'ws'):
             add_one_type_printer(obj, abi + 'match_results', abi + ch + 'match')
             for x in ('sub_match', 'regex_iterator', 'regex_token_iterator'):
@@ -2170,9 +2184,13 @@ def register_type_printers(obj):
 
     # Add type printers for experimental::basic_string_view typedefs.
     ns = 'experimental::fundamentals_v1::'
-    for ch in ('', 'w', 'u8', 'u16', 'u32'):
+    for ch in (('', 'char'),
+               ('w', 'wchar_t'),
+               ('u8', 'char8_t'),
+               ('u16', 'char16_t'),
+               ('u32', 'char32_t')):
         add_one_type_printer(obj, ns + 'basic_string_view',
-                             ns + ch + 'string_view')
+                             ns + ch[0] + 'string_view', ch[1])
 
     # Do not show defaulted template arguments in class templates.
     add_one_template_type_printer(obj, 'unique_ptr',

^ permalink raw reply	[flat|nested] 8+ messages in thread
end of thread, other threads:[~2022-11-17  5:28 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-10-06 17:38 [PATCH] Fix gdb FilteringTypePrinter (again) François Dumont
2022-11-14 17:57 ` François Dumont
2022-11-15 16:17 ` Jonathan Wakely
2022-11-16  6:04   ` François Dumont
2022-11-16 11:35     ` Jonathan Wakely
2022-11-16 11:54       ` Jonathan Wakely
2022-11-16 12:29         ` Jonathan Wakely
2022-11-17  5:28         ` François Dumont

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