15 Commits

Author SHA1 Message Date
Matheus Izvekov
14f7bd63b9
Reland: [clang] preserve class type sugar when taking pointer to member (#132401)
Original PR: #130537
Originally reverted due to revert of dependent commit. Relanding with no
changes.

This changes the MemberPointerType representation to use a
NestedNameSpecifier instead of a Type to represent the base class.

Since the qualifiers are always parsed as nested names, there was an
impedance mismatch when converting these back and forth into types, and
this led to issues in preserving sugar.

The nested names are indeed a better match for these, as the differences
which a QualType can represent cannot be expressed syntatically, and
they represent the use case more exactly, being either dependent or
referring to a CXXRecord, unqualified.

This patch also makes the MemberPointerType able to represent sugar for
a {up/downcast}cast conversion of the base class, although for now the
underlying type is canonical, as preserving the sugar up to that point
requires further work.

As usual, includes a few drive-by fixes in order to make use of the
improvements.
2025-03-21 13:20:52 -03:00
Matheus Izvekov
5151e6d7fe
Revert "Reland: [clang] preserve class type sugar when taking pointer to member" (#132280)
Reverts llvm/llvm-project#132234

Needs to be reverted due to dependency.

This blocks reverting another PR, see here:
https://github.com/llvm/llvm-project/pull/131965#issuecomment-2741619498
2025-03-20 17:52:48 -03:00
Matheus Izvekov
578f38cd08
Reland: [clang] preserve class type sugar when taking pointer to member (#132234)
Original PR: #130537
Reland after updating lldb too.

This changes the MemberPointerType representation to use a
NestedNameSpecifier instead of a Type to represent the base class.

Since the qualifiers are always parsed as nested names, there was an
impedance mismatch when converting these back and forth into types, and
this led to issues in preserving sugar.

The nested names are indeed a better match for these, as the differences
which a QualType can represent cannot be expressed syntatically, and
they represent the use case more exactly, being either dependent or
referring to a CXXRecord, unqualified.

This patch also makes the MemberPointerType able to represent sugar for
a {up/downcast}cast conversion of the base class, although for now the
underlying type is canonical, as preserving the sugar up to that point
requires further work.

As usual, includes a few drive-by fixes in order to make use of the
improvements.
2025-03-20 15:33:54 -03:00
Matheus Izvekov
6cd62ad08c
Revert "[clang] improve class type sugar preservation in pointers to members" (#132215)
Reverts llvm/llvm-project#130537

This missed updating lldb, which we didn't notice due to lack of
pre-commit CI.
2025-03-20 11:09:25 -03:00
Matheus Izvekov
9b1f905b48
[clang] improve class type sugar preservation in pointers to members (#130537)
This changes the MemberPointerType representation to use a
NestedNameSpecifier instead of a Type to represent the class.

Since the qualifiers are always parsed as nested names, there was an
impedance mismatch when converting these back and forth into types, and
this led to issues in preserving sugar.

The nested names are indeed a better match for these, as the differences
which a QualType can represent cannot be expressed syntactically, and it
also represents the use case more exactly, being either dependent or
referring to a CXXRecord, unqualified.

This patch also makes the MemberPointerType able to represent sugar for
a {up/downcast}cast conversion of the base class, although for now the
underlying type is canonical, as preserving the sugar up to that point
requires further work.

As usual, includes a few drive-by fixes in order to make use of the
improvements, and removing some duplications, for example
CheckBaseClassAccess is deduplicated from across SemaAccess and
SemaCast.
2025-03-20 10:30:24 -03:00
Nikita Popov
07f3388fff Revert "[clang] Implement instantiation context note for checking template parameters (#126088)"
This reverts commit a24523ac8dc07f3478311a5969184b922b520395.

This is causing significant compile-time regressions for C++ code, see:
https://github.com/llvm/llvm-project/pull/126088#issuecomment-2704874202
2025-03-10 10:32:08 +01:00
Matheus Izvekov
a24523ac8d
[clang] Implement instantiation context note for checking template parameters (#126088)
Instead of manually adding a note pointing to the relevant template
parameter to every relevant error, which is very easy to miss, this
patch adds a new instantiation context note, so that this can work using
RAII magic.

This fixes a bunch of places where these notes were missing, and is more
future-proof.

Some diagnostics are reworked to make better use of this note:
- Errors about missing template arguments now refer to the parameter
which is missing an argument.
- Template Template parameter mismatches now refer to template
parameters as parameters instead of arguments.

It's likely this will add the note to some diagnostics where the
parameter is not super relevant, but this can be reworked with time and
the decrease in maintenance burden makes up for it.

This bypasses the templight dumper for the new context entry, as the
tests are very hard to update.

This depends on #125453, which is needed to avoid losing the context
note for errors occuring during template argument deduction.
2025-03-06 14:58:42 -03:00
David Majnemer
cd053cd5ed Sema: Enforce C++11 pointer-to-member template arguments should rules
The standard is pretty clear on what it allows inside of template
arguments for non-type template parameters of pointer-to-member.

They must be of the form &qualified-id and cannot come from sources like
constexpr VarDecls or things of that nature.

This fixes PR18192.

llvm-svn: 196852
2013-12-10 00:40:58 +00:00
Chandler Carruth
a92409c3ec Enhance the diagnostic for negative array sizes to include the
declaration name of the array when present. This ensures that
a poor-man's C++03 static_assert will include the user error message
often embedded in the name.

Update all the tests to reflect the new wording, and add a test for the
name behavior.

llvm-svn: 122802
2011-01-04 04:44:35 +00:00
Douglas Gregor
0e4de76610 A DeclRefExpr that refers to a member function or a static data member
of the current instantiation is value-dependent. The C++ standard
fails to enumerate this case and, therefore, we missed it. Chandler
did all of the hard work of reducing the last remaining
Boost.PtrContainer failure (which had to do with static initialization
in the Serialization library) down to this simple little test.

While I'm at it, clean up the dependence rules for template arguments
that are declarations, and implement the dependence rules for template
argument packs.

llvm-svn: 103464
2010-05-11 08:41:30 +00:00
Daniel Dunbar
8fbe78f6fc Update tests to use %clang_cc1 instead of 'clang-cc' or 'clang -cc1'.
- This is designed to make it obvious that %clang_cc1 is a "test variable"
   which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
   can be useful to redefine what gets run as 'clang -cc1' (for example, to set
   a default target).

llvm-svn: 91446
2009-12-15 20:14:24 +00:00
Douglas Gregor
2bb756a3be Template argument deduction of a non-type template parameter from a
template argument.

llvm-svn: 88722
2009-11-13 23:45:44 +00:00
Douglas Gregor
49ba3cabdd Recognize (and check) pointer-to-member template arguments that are
non-type template parameters or constants of pointer-to-member
type. Once checked, be sure to retain those pointer-to-member
constants as expressions if they are dependent, or as declarations if
they are not dependent.

llvm-svn: 87010
2009-11-12 18:38:13 +00:00
Douglas Gregor
4e948ce769 When instantiating a reference to a non-type template parameter of pointer to
member type (e.g., T Class::*Member), build a pointer-to-member
constant expression. Previously, we we just building a simple
declaration reference expression, which meant that the expression was
not treated as a pointer to member.

llvm-svn: 87000
2009-11-12 17:40:13 +00:00
Douglas Gregor
0bdc1f5eef Handle member pointer types with dependent class types (e.g., int
T::*) and implement template instantiation for member pointer types.

llvm-svn: 73151
2009-06-09 22:17:39 +00:00