30842 Commits

Author SHA1 Message Date
David Blaikie
ec273d3e3a Add a warning for not packing non-POD members in packed structs
Differential Revision: https://reviews.llvm.org/D118511
2022-10-26 22:18:51 +00:00
David Blaikie
7846d59003 Extend the C++03 definition of POD to include defaulted functions
The AST/conditionally-trivial-smfs tests look a bit questionable, but
are consistent with GCC's POD-ness, at least as far as packing is
concerned: https://godbolt.org/z/36nqPMbKM
(questionable because it looks like the type would be non-copyable, so
how could it be pod? But the calling convention/pass by value seems to
work correctly (local testing verifies that this behavior is preserved
even with this patch: https://godbolt.org/z/3Pa89zsv6 ))

Differential Revision: https://reviews.llvm.org/D119051
2022-10-26 22:00:49 +00:00
Sami Tolvanen
1aad641c79 [Clang][Sema] Add -Wcast-function-type-strict
Clang supports indirect call Control-Flow Integrity (CFI) sanitizers
(e.g. -fsanitize=cfi-icall), which enforce an exact type match between
a function pointer and the target function. Unfortunately, Clang
doesn't provide diagnostics that would help developers avoid function
type casts that lead to runtime CFI failures. -Wcast-function-type,
while helpful, only warns about ABI incompatibility, which isn't
sufficient with CFI.

Add -Wcast-function-type-strict, which checks for a strict type
compatibility in function type casts and helps warn about casts that
can potentially lead to CFI failures.

Reviewed By: nickdesaulniers, aaron.ballman

Differential Revision: https://reviews.llvm.org/D134831
2022-10-26 20:38:37 +00:00
Ben Langmuir
211f5af38a [clang] Move getenv call for SOURCE_DATE_EPOCH out of frontend NFC
Move the check for SOURCE_DATE_EPOCH to the driver and use a cc1 option
to pass it to the frontend. This avoids hidden state in the cc1
invocation and makes this env variable behave more like other env
variables that clang handles in the driver.

Differential Revision: https://reviews.llvm.org/D136717
2022-10-26 12:42:56 -07:00
Sam McCall
e044824567 [Lex] Stop allocating/deallocating MacroInfo on a linked list. NFC
This list was originally used for to make sure MacroInfo's clever memory
management got called (1f1e4bdbf7815c), but that was
simplified in 73a29662b9bf640a and 1f1e4bdbf7815c, and there's nothing left.

Differential Revision: https://reviews.llvm.org/D136725
2022-10-26 16:24:25 +02:00
Gabor Marton
bb72d0dde2 [clang][dataflow] Implement transferBranch
This patch introduces `transferBranch`, which Applies the analysis
transfer function for a given edge from a CFG block of a conditional
statement.

RFC:
https://discourse.llvm.org/t/rfc-clang-dataflow-signanalysis-edgetransfer-branchtransfer/65220

Differential Revision: https://reviews.llvm.org/D133698
2022-10-26 15:24:55 +02:00
Matheus Izvekov
b1f1ce782c
Revert "[clang] Changes to produce sugared converted template arguments"
This reverts commit 11ce78940b4c6f44ae6ee5a6611d6c9b1bade1c2.
2022-10-26 10:14:40 +02:00
Matheus Izvekov
8383c2a435
Revert "[clang] Implement sugared substitution changes to infrastructure"
This reverts commit c4c2a3c65684e062efcd101a957c6cae0a304a7a.
2022-10-26 10:14:31 +02:00
Matheus Izvekov
a88ebd405d
Revert "[clang] Instantiate NTTPs and template default arguments with sugar"
This reverts commit 2560c1266993af6e6c15900ce673c6db23132f8b.
2022-10-26 10:14:27 +02:00
Matheus Izvekov
2560c12669
[clang] Instantiate NTTPs and template default arguments with sugar
This makes use of the changes introduced in D134604, in order to
instantiate non-type template parameters and default template arguments
with a final sugared substitution.

This comes at no additional relevant cost.
Since we don't track / unique them in specializations, we wouldn't be
able to resugar them later anyway.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D136564
2022-10-26 03:22:22 +02:00
Matheus Izvekov
c4c2a3c656
[clang] Implement sugared substitution changes to infrastructure
Implements the changes required to perform substitution with
non-canonical template arguments, and to 'finalize' them
by not placing 'Subst' nodes.

A finalized substitution means we won't resugar them later,
because these templates themselves were eagerly substituted
with the intended arguments at the point of use. We may still
resugar other templates used within those, though.

This patch does not actually implement any uses of this
functionality, those will be added in subsequent patches,
so expect no changes to existing tests.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D134604
2022-10-26 03:21:15 +02:00
Matheus Izvekov
11ce78940b
[clang] Changes to produce sugared converted template arguments
Makes CheckTemplateArgumentList and the template deduction functions
produce a sugared converted argument list in addition to the canonical one.

This is mostly NFC except that we hook this up to a few diagnostics in
SemaOverload.

The infrastructure here will be used in subsequent patches
where we perform a finalized sugared substitution for entities
which we do not unique per specializations on canonical arguments,
and later on will be used for template specialization resugaring.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D133874
2022-10-26 02:15:10 +02:00
Sam McCall
d03ee70de1 [Tooling] Avoid StandardLibrary.h including Decl. NFC
So you can use the enum in a header without pulling in half the AST.
2022-10-25 19:12:45 +02:00
Nico Weber
60809cd293 Revert "[clang] Fix missing diagnostic of declaration use when accessing TypeDecls through typename access"
This reverts commit dc170433137aeda5e5276bd292cac12aa93fee7c.
Breaks building LLVM on mac when targeting macOS before 10.15, see
comments on https://reviews.llvm.org/D136533
2022-10-25 12:23:10 -04:00
David Green
af1bb287b4 [AArch64][ARM] Alter v8.3a complex neon intrinsics to be target-based, not preprocessor based
This alters the 8.3 complex intrinsics to be target-gated, as opposed to
hidden behind preprocessor macros. This is the last of arm_neon.h, and
follows the same formula as before.

Differential Revision: https://reviews.llvm.org/D135647
2022-10-25 14:35:11 +01:00
Daniel Grumberg
791fe26d75 [clang][ExtractAPI] Allow users to specify a list of symbols to ignore
Adds a `--extract-api-ignores=` command line option that allows users to
provide a file containing a new line separated list of symbols to
unconditionally ignore when extracting API information.

Differential Revision: https://reviews.llvm.org/D136450
2022-10-25 11:46:04 +01:00
David Green
9c48b7f0e7 [AArch64][ARM] Alter v8.1a neon intrinsics to be target-based, not preprocessor based
As a continuation of D132034, this switches the QRDMX v8.1a neon
intrinsics over from preprocessor defines to be target-gated. As there
is no "rdma" or "qrdmx" target feature, they use the "v8.1a"
architecture feature directly.

This works well for AArch64, but something needs to be done for Arm at
the same time, as they both use the same header and tablegen emitter.
This patch opts for adding "v8.1a" and all dependant target features to
the Arm TargetParser, similar to what was recently done for AArch64 but
through initFeatureMap when the Architecture is parsed. I attempted to
make the code similar to the AArch64 backend.

Otherwise this is similar to the changes made in D132034.

Differential Revision: https://reviews.llvm.org/D135615
2022-10-25 09:02:52 +01:00
Fangrui Song
3a3603ff99 [clang] Replace BACKEND_PACKAGE_STRING with LLVM_VERSION_STRING
420d7ccbac0f499a6ff9595bdbfa99cd3376df22 introduced BACKEND_PACKAGE_STRING to
replace `PACKAGE_VERSION` (llvm/Config/config.h) to support standalone builds.
This is used in the output of `clang -cc1 -v`.

Since llvm-config.h is available for both standalone and non-standalone builds,
we can just use `LLVM_VERSION_STRING` from llvm-config.h.

clang/cmake/modules/AddClang.cmake uses `VERSION_STRING "${CLANG_VERSION} (${BACKEND_PACKAGE_STRING})"`.
Just simplify it to `"${CLANG_VERSION}"` so that we can remove the CMake
variable BACKEND_PACKAGE_STRING.

Reviewed By: tstellar

Differential Revision: https://reviews.llvm.org/D136660
2022-10-25 00:24:25 -07:00
Freddy Ye
fdac4c4e92 [X86] Add CMPCCXADD instructions.
For more details about these instructions, please refer to the latest ISE document: https://www.intel.com/content/www/us/en/develop/download/intel-architecture-instruction-set-extensions-programming-reference.html

Reviewed By: pengfei, skan

Differential Revision: https://reviews.llvm.org/D135933
2022-10-25 14:33:39 +08:00
Matheus Izvekov
dc17043313
[clang] Fix missing diagnostic of declaration use when accessing TypeDecls through typename access
Fixes GH58547.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D136533
2022-10-25 02:46:35 +02:00
Matheus Izvekov
1acffe81ee
NFC: [clang] Template argument cleanups.
Removes a bunch of obsolete methods in favor of a single one returning
an ArrayRef of TemplateArgument.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D136602
2022-10-25 00:29:56 +02:00
Craig Topper
c3ead85e2f [RISCV][clang] Support RISC-V vectors in UninitializedValues.
RISC-V vectors are basically vectors, but we use builtin types to
restrict the possible types. Treat them the same as vectors and scalars
for this analysis.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D136511
2022-10-24 12:38:32 -07:00
Erich Keane
975740bf8d "Reapply "GH58368: Correct concept checking in a lambda defined in concept""
This reverts commit cecc9a92cfca71c1b6c2a35c5e302ab649496d11.

The problem ended up being how we were handling the lambda-context in
code generation: we were assuming any decl context here would be a
named-decl, but that isn't the case.  Instead, we just replace it with
the concept's owning context.

Differential Revision: https://reviews.llvm.org/D136451
2022-10-24 12:36:54 -07:00
Björn Schäpers
006bf8d817 [clang-format][NFC] Handle language specific stuff at the top...
... of TokenAnnotator::splitPenalty. That is in my eyes a bit clearer
in the workflow.

As a drive-by introduce (but not adapt anywhere else) isProto().

Differential Revision: https://reviews.llvm.org/D135871
2022-10-24 21:28:13 +02:00
Erich Keane
cecc9a92cf Revert "Reapply "GH58368: Correct concept checking in a lambda defined in concept"""
This reverts commit b876f6e2f28779211a829d7d4e841fe68885ae20.

Still getting build failures on PPC AIX that aren't obvious what is causing
them, so reverting while I try to figure this out.
2022-10-24 12:20:23 -07:00
Erich Keane
b876f6e2f2 Reapply "GH58368: Correct concept checking in a lambda defined in concept""
This reverts commit 52930162870fee52d0d9c07c5d66e5dce32b08e8.

Now with updating the ASTBitcodes to show that this AST is incompatible
from the last.
2022-10-24 11:46:54 -07:00
Erich Keane
5293016287 Revert "GH58368: Correct concept checking in a lambda defined in concept"
This reverts commit b7c922607c5ba93db8b893d4ba461052af8317b5.

This seems to cause some problems with some modules related things,
which makes me think I should have updated the version-major in
ast-bit-codes?  Going to revert to confirm this was a problem, then
change that and re-try a commit.
2022-10-24 10:21:22 -07:00
Corentin Jabot
d0d2772379 [Clang] Implement P2513
Implement P2513

This change allows initializing an array of unsigned char,
or char from u8 string literals.
This was done both to support legacy code and for compatibility
with C where char8_t will be typedef to unsigned char.

This is backported to C++20 as per WG21 guidance.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D136449
2022-10-24 18:10:43 +02:00
Erich Keane
b7c922607c GH58368: Correct concept checking in a lambda defined in concept
As that bug reports, the problem here is that the lambda's
'context-decl' was not set to the concept, and the lambda picked up
template arguments from the concept.  SO, we failed to get the correct
template arguments in SemaTemplateInstantiate.

However, a Concept Specialization is NOT a decl, its an expression, so
we weren't able to put the concept in the decl tree like we needed.
This patch introduces a ConceptSpecializationDecl, which is the smallest
type possible to use for this purpose, containing only the template
arguments.

The net memory impliciation of this is turning a
trailing-objects into a pointer to a type with trailing-objects,  so it
should be minor.

As future work, we may consider giving this type more responsibility, or
figuring out how to better merge duplicates, but as this is just a
template-argument collection at the moment, there isn't much value to
it.

Differential Revision: https://reviews.llvm.org/D136451
2022-10-24 06:32:18 -07:00
David Green
6f1e430360 [AArch64] Alter v8.5a FRINT neon intrinsics to be target-based, not preprocessor based
This switches the v8.5-a FRINT intrinsics over to be target-gated,
behind preprocessor defines. This one is pretty simple, being AArch64
only.

Differential Revision: https://reviews.llvm.org/D135646
2022-10-24 11:22:06 +01:00
Rong Xu
6cee539337 [Clang] Change AnonStructIds in MangleContext to per-function based
Clang is generating different mangled names for the same lambda
function in slightly changed builds (like with non-related
source/Macro change). This is due to the fact that clang uses a
cross-translation-unit sequential string "$_<n>" in lambda's
mangled name. Here, "n" is the AnonStructIds field in MangleContext.

Different mangled names for a unchanged function is undesirable:
it makes perf comparison harder, and can cause some unnecessary
profile mismatch in SampleFDO.

This patch makes mangled name for lambda functions more stable
by changing AnonStructIds to a per-function based seq number if the
DeclContext is a function.

Differential Revision: https://reviews.llvm.org/D136397
2022-10-23 22:33:52 -07:00
Xiang1 Zhang
661881d436 [X86] Add AMX-FP16 instructions.
Differential Revision: https://reviews.llvm.org/D135941
2022-10-22 08:05:22 +08:00
Erich Keane
a726be3875 [NFC] Make sure we check an optional when checking function constraints
For some reason the initial deferred concepts patch didn't add this
check, which someone noticed could cause a problem with other patches
applied.  This makes sure we check these, so that an error condition
cannot cause us to crash.
2022-10-21 07:32:57 -07:00
Luo, Yuanke
3770d2b9ca [X86] Fix typo of mtamx_int8 2022-10-21 21:13:07 +08:00
Evgeny Shulgin
5b567637e2 [Clang] Add __has_constexpr_builtin support
The `__has_constexpr_builtin` macro can be used to check
whether the builtin in constant-evaluated by Clang frontend.

Reviewed By: aaron.ballman, shafik

Differential Revision: https://reviews.llvm.org/D136036
2022-10-21 11:23:10 +00:00
Danil Sidoruk
9c422ab7ce
[clang-format] Add option for aligning requires clause body
Adds an option whether requires clause body should be aligned with
the `requires` keyword.
This option is now the default, both without configuration and in LLVM
style.

Fixes https://github.com/llvm/llvm-project/issues/56283

Differential Revision: https://reviews.llvm.org/D129443

Co-authored-by: Emilia Dreamer <emilia@rymiel.space>
2022-10-21 10:42:45 +03:00
Xiang Li
464926ef44 [HLSL] Disable integer promotion to avoid int16_t being promoted to int for HLSL.
short will be promoted to int in UsualUnaryConversions.
Disable it for HLSL to keep int16_t as 16bit.

Reviewed By: aaron.ballman, rjmccall

Differential Revision: https://reviews.llvm.org/D133668
2022-10-20 16:06:25 -07:00
Xiang Li
a7183a158d [NFC] [DirectX backend] move ResourceClass into llvm.
Move ResourceClass into llvm/Frontend/HLSL/HLSLResource.h so it could be shared between clang and DirectX backend.

Reviewed By: beanz

Differential Revision: https://reviews.llvm.org/D136134
2022-10-20 13:26:56 -07:00
Bill Wendling
b76219b590 [clang][Sema] Use correct array size for diagnostic
The diagnostic was confusing and reporting that an array contains far
more elements than it is defined to have, due to casting.

For example, this code:

  double foo[4096];
  ((char*)foo)[sizeof(foo)];

warns that the "index 32768 is past the end of the array (which contains
32768 elements)."

Reviewed By: serge-sans-paille, aaron.ballman

Differential Revision: https://reviews.llvm.org/D135920
2022-10-20 11:56:49 -07:00
Xiang Li
7e04c0ad63 [HLSL] Add groupshare address space.
Added keyword, LangAS and TypeAttrbute for groupshared.

Tanslate it to LangAS with asHLSLLangAS.

Make sure it translated into address space 3 for DirectX target.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D135060
2022-10-20 09:29:09 -07:00
Paul Walker
ab8257ca0e [NFC] Fix a few whitespace inconsistencies. 2022-10-20 14:52:25 +00:00
Phoebe Wang
62ca79102c [X86][1/2] Support PREFETCHI instructions
For more details about these instructions, please refer to the latest ISE document: https://www.intel.com/content/www/us/en/develop/download/intel-architecture-instruction-set-extensions-programming-reference.html

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D136040
2022-10-20 08:46:01 +08:00
Eli Friedman
795f67934d [Sema] Don't treat a non-null template argument as if it were null.
The way this code checks whether a pointer is null is wrong for other
reasons; it doesn't actually check whether a null pointer constant is a
"constant" in the C++ standard sense.  But this fix at least makes sure
we don't treat a non-null pointer as if it were null.

Fixes https://github.com/llvm/llvm-project/issues/57883

Differential Revision: https://reviews.llvm.org/D134928
2022-10-19 14:40:52 -07:00
Phoebe Wang
bc1819389f [X86][RFC] Using __bf16 for AVX512_BF16 intrinsics
This is an alternative of D120395 and D120411.

Previously we use `__bfloat16` as a typedef of `unsigned short`. The
name may give user an impression it is a brand new type to represent
BF16. So that they may use it in arithmetic operations and we don't have
a good way to block it.

To solve the problem, we introduced `__bf16` to X86 psABI and landed the
support in Clang by D130964. Now we can solve the problem by switching
intrinsics to the new type.

Reviewed By: LuoYuanke, RKSimon

Differential Revision: https://reviews.llvm.org/D132329
2022-10-19 23:47:04 +08:00
Tomasz Kamiński
a6b42040ad [analyzer] Fix the liveness of Symbols for values in regions referred by LazyCompoundVal
To illustrate our current understanding, let's start with the following program:
https://godbolt.org/z/33f6vheh1
```lang=c++
void clang_analyzer_printState();

struct C {
   int x;
   int y;
   int more_padding;
};

struct D {
   C c;
   int z;
};

C foo(D d, int new_x, int new_y) {
   d.c.x = new_x;       // B1
   assert(d.c.x < 13);  // C1

   C c = d.c;           // L

   assert(d.c.y < 10);  // C2
   assert(d.z < 5);     // C3

   d.c.y = new_y;       // B2

   assert(d.c.y < 10);  // C4

   return c;  // R
}
```
In the code, we create a few bindings to subregions of root region `d` (`B1`, `B2`), a constrain on the values  (`C1`, `C2`, ….), and create a `lazyCompoundVal` for the part of the region `d` at point `L`, which is returned at point `R`.

Now, the question is which of these should remain live as long the return value of the `foo` call is live. In perfect a word we should preserve:

  # only the bindings of the subregions of `d.c`, which were created before the copy at `L`. In our example, this includes `B1`, and not `B2`.  In other words, `new_x` should be live but `new_y` shouldn’t.

  # constraints on the values of `d.c`, that are reachable through `c`. This can be created both before the point of making the copy (`L`) or after. In our case, that would be `C1` and `C2`. But not `C3` (`d.z` value is not reachable through `c`) and `C4` (the original value of`d.c.y` was overridden at `B2` after the creation of `c`).

The current code in the `RegionStore` covers the use case (1), by using the `getInterestingValues()` to extract bindings to parts of the referred region present in the store at the point of copy. This also partially covers point (2), in case when constraints are applied to a location that has binding at the point of the copy (in our case `d.c.x` in `C1` that has value `new_x`), but it fails to preserve the constraints that require creating a new symbol for location (`d.c.y` in `C2`).

We introduce the concept of //lazily copied// locations (regions) to the `SymbolReaper`, i.e. for which a program can access the value stored at that location, but not its address. These locations are constructed as a set of regions referred to by `lazyCompoundVal`. A //readable// location (region) is a location that //live// or //lazily copied// . And symbols that refer to values in regions are alive if the region is //readable//.

For simplicity, we follow the current approach to live regions and mark the base region as //lazily copied//, and consider any subregions as //readable//. This makes some symbols falsy live (`d.z` in our example) and keeps the corresponding constraints alive.

The rename `Regions` to `LiveRegions` inside  `RegionStore` is NFC change, that was done to make it clear, what is difference between regions stored in this two sets.

Regression Test: https://reviews.llvm.org/D134941
Co-authored-by: Balazs Benics <benicsbalazs@gmail.com>

Reviewed By: martong, xazax.hun

Differential Revision: https://reviews.llvm.org/D134947
2022-10-19 16:06:32 +02:00
Yitzhak Mandelbaum
8cadac41e9 [clang][dataflow] Add equivalence relation Value type.
Defines an equivalence relation on the `Value` type to standardize several
places in the code where we replicate the ~same equivalence comparison.

Differential Revision: https://reviews.llvm.org/D135964
2022-10-19 12:23:09 +00:00
Alexey Bader
66bd6074c1 [Attr][Doc] Fix pragma unroll documentation.
There is a contradiction in the #pragma unroll behavior documentation.
It says that specifying `#pragma unroll` without a parameter directs the
loop unroller to attempt to partially unroll the loop if the trip count
is not known at compile time. At the same time later it states that
`#pragma unroll` has identical semantics to `#pragma clang loop unroll(full)`,
which doesn't attempt to unroll partially if the trip count is not known
at compile time.

pragma clang loop unroll(enable):
If unroll(enable) is specified the unroller will attempt to fully unroll
the loop if the trip count is known at compile time. If the fully
unrolled code size is greater than an internal limit the loop will be
partially unrolled up to this limit. If the trip count is not known at
compile time the loop will be partially unrolled with a heuristically
chosen unroll factor.

pragma clang loop unroll(full):
If unroll(full) is specified the unroller will attempt to fully unroll
the loop if the trip count is known at compile time identically to
unroll(enable). However, with unroll(full) the loop will not be unrolled
if the loop count is not known at compile time.

Differential Revision: https://reviews.llvm.org/D136160
2022-10-19 03:50:47 -07:00
Serge Pavlov
0dec5e164f Keep configuration file search directories in ExpansionContext. NFC
Class ExpansionContext encapsulates options for search and expansion of
response files, including configuration files. With this change the
directories which are searched for configuration files are also stored
in ExpansionContext.

Differential Revision: https://reviews.llvm.org/D135439
2022-10-19 17:20:14 +07:00
Xiang Li
14ae5d2b74 [HLSL] Add SV_DispatchThreadID
Support SV_DispatchThreadID attribute.
Translate it into dx.thread.id in clang codeGen.

Reviewed By: beanz, aaron.ballman

Differential Revision: https://reviews.llvm.org/D133983
2022-10-18 16:17:19 -07:00
Yuanfang Chen
340eac01f7 [C++20] Implement P2113R0: Changes to the Partial Ordering of Constrained Functions
This implementation matches GCC behavior in that [[ https://eel.is/c++draft/temp.func.order#6.2.1 | temp.func.order p6.2.1 ]] is not implemented [1]. I reached out to the GCC author to confirm that some changes elsewhere to overload resolution are probably needed, but no solution has been developed sufficiently [3].

Most of the wordings are implemented straightforwardly. However,
for [[ https://eel.is/c++draft/temp.func.order#6.2.2 | temp.func.order p6.2.2 ]] "... or if the function parameters that positionally correspond between the two templates are not of the same type", the "same type" is not very clear ([2] is a bug related to this). Here is a quick example
```
template <C T, C U>        int f(T, U);
template <typename T, C U> int f(U, T);

int x = f(0, 0);
```
Is the `U` and `T` from different `f`s the "same type"? The answer is NO even though both `U` and `T` are deduced to be `int` in this case. The reason is that `U` and `T` are dependent types, according to [[ https://eel.is/c++draft/temp.over.link#3 |  temp.over.link p3 ]], they can not be the "same type".

To check if two function parameters are the "same type":
* For //function template//: compare the function parameter canonical types and return type between two function templates.
* For //class template/partial specialization//: by [[ https://eel.is/c++draft/temp.spec.partial.order#1.2 | temp.spec.partial.order p1.2 ]], compare the injected template arguments between two templates using hashing(TemplateArgument::Profile) is enough.

[1] https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=57b4daf8dc4ed7b669cc70638866ddb00f5b7746
[2] https://github.com/llvm/llvm-project/issues/49308
[3] https://lists.isocpp.org/core/2020/06/index.php#msg9392

Fixes https://github.com/llvm/llvm-project/issues/54039
Fixes https://github.com/llvm/llvm-project/issues/49308 (PR49964)

Reviewed By: royjacobson, #clang-language-wg, mizvekov

Differential Revision: https://reviews.llvm.org/D128750
2022-10-18 11:58:57 -07:00