Commit Graph

5181 Commits

Author SHA1 Message Date
Aaron Puchert ce7eb72a3c Thread safety analysis: Reword warning after D72635
We allow arbitrary names for capabilities now, and the name didn't play
a role for this anyway.
2020-04-27 22:23:52 +02:00
Aaron Puchert f43859a099 PR45000: Let Sema::SubstParmVarDecl handle default args of lambdas in initializers
Summary:
We extend the behavior for local functions and methods of local classes
to lambdas in variable initializers. The initializer is not a separate
scope, but we treat it as such.

We also remove the (faulty) instantiation of default arguments in
TreeTransform::TransformLambdaExpr, because it doesn't do proper
initialization, and if it did, we would do it twice (and thus also emit
eventual errors twice).

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D76038
2020-04-22 22:37:21 +02:00
Haojian Wu 89d9912cbf [AST] dont invaliate VarDecl when the initializer contains errors.
Summary:
This patch contains 2 separate changes:
1) the initializer of a variable should play no part in decl "invalid" bit;
2) preserve the invalid initializer via recovery exprs;

With 1), we will regress the diagnostics (one big regression is that we loose
the "selected 'begin' function with iterator type" diagnostic in for-range stmt;
but with 2) together, we don't have regressions (the new diagnostics seems to be
improved).

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78116
2020-04-21 10:53:35 +02:00
Haojian Wu e90fb82f0f [AST] Suppress the spammy "attempt to use a deleted fucntion" diagnostic.
Summary:
This patch fixes the regression diagnostic, which was introduced in
https://reviews.llvm.org/D77395.

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: rsmith, adamcz, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78100
2020-04-21 09:43:46 +02:00
Richard Smith 4b03dd7b84 PR45534: don't ignore unmodeled side-effects when constant-evaluating a call to __builtin_constant_p.
Such side-effects should result in the call evaluating to 'false', even
if we can still determine what value the argument expression will
evaluate to.
2020-04-20 21:23:35 -07:00
Erich Keane 5f0903e9be Reland Implement _ExtInt as an extended int type specifier.
I fixed the LLDB issue, so re-applying the patch.

This reverts commit a4b88c0449.
2020-04-17 10:45:48 -07:00
Sterling Augustine a4b88c0449 Revert "Implement _ExtInt as an extended int type specifier."
This reverts commit 61ba1481e2.

I'm reverting this because it breaks the lldb build with
incomplete switch coverage warnings. I would fix it forward,
but am not familiar enough with lldb to determine the correct
fix.

lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:3958:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
          ^
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:4633:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
          ^
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:4889:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
2020-04-17 10:29:40 -07:00
Erich Keane 61ba1481e2 Implement _ExtInt as an extended int type specifier.
Introduction/Motivation:
LLVM-IR supports integers of non-power-of-2 bitwidth, in the iN syntax.
Integers of non-power-of-two aren't particularly interesting or useful
on most hardware, so much so that no language in Clang has been
motivated to expose it before.

However, in the case of FPGA hardware normal integer types where the
full bitwidth isn't used, is extremely wasteful and has severe
performance/space concerns.  Because of this, Intel has introduced this
functionality in the High Level Synthesis compiler[0]
under the name "Arbitrary Precision Integer" (ap_int for short). This
has been extremely useful and effective for our users, permitting them
to optimize their storage and operation space on an architecture where
both can be extremely expensive.

We are proposing upstreaming a more palatable version of this to the
community, in the form of this proposal and accompanying patch.  We are
proposing the syntax _ExtInt(N).  We intend to propose this to the WG14
committee[1], and the underscore-capital seems like the active direction
for a WG14 paper's acceptance.  An alternative that Richard Smith
suggested on the initial review was __int(N), however we believe that
is much less acceptable by WG14.  We considered _Int, however _Int is
used as an identifier in libstdc++ and there is no good way to fall
back to an identifier (since _Int(5) is indistinguishable from an
unnamed initializer of a template type named _Int).

[0]https://www.intel.com/content/www/us/en/software/programmable/quartus-prime/hls-compiler.html)
[1]http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2472.pdf

Differential Revision: https://reviews.llvm.org/D73967
2020-04-17 07:10:57 -07:00
Aaron Ballman 2ec5520a54 Disallow [[nodiscard]] on a function pointer declaration.
This is not allowed by [dcl.attr.nodiscard]p1 for the standard attribute, but
is still supported for the [[clang::warn_unused_result]] spelling.
2020-04-16 09:28:49 -04:00
Richard Smith 57acbaece1 Improve diagnostic when constant-evaluating a std::initializer_list with
an unexpected form.
2020-04-15 13:28:24 -07:00
Richard Smith bab6df86ae Rework how UuidAttr, CXXUuidofExpr, and GUID template arguments and constants are represented.
Summary:
Previously, we treated CXXUuidofExpr as quite a special case: it was the
only kind of expression that could be a canonical template argument, it
could be a constant lvalue base object, and so on. In addition, we
represented the UUID value as a string, whose source form we did not
preserve faithfully, and that we partially parsed in multiple different
places.

With this patch, we create an MSGuidDecl object to represent the
implicit object of type 'struct _GUID' created by a UuidAttr. Each
UuidAttr holds a pointer to its 'struct _GUID' and its original
(as-written) UUID string. A non-value-dependent CXXUuidofExpr behaves
like a DeclRefExpr denoting that MSGuidDecl object. We cache an APValue
representation of the GUID on the MSGuidDecl and use it from constant
evaluation where needed.

This allows removing a lot of the special-case logic to handle these
expressions. Unfortunately, many parts of Clang assume there are only
a couple of interesting kinds of ValueDecl, so the total amount of
special-case logic is not really reduced very much.

This fixes a few bugs and issues:
 * PR38490: we now support reading from GUID objects returned from
   __uuidof during constant evaluation.
 * Our Itanium mangling for a non-instantiation-dependent template
   argument involving __uuidof no longer depends on which CXXUuidofExpr
   template argument we happened to see first.
 * We now predeclare ::_GUID, and permit use of __uuidof without
   any header inclusion, better matching MSVC's behavior. We do not
   predefine ::__s_GUID, though; that seems like a step too far.
 * Our IR representation for GUID constants now uses the correct IR type
   wherever possible. We will still fall back to using the
      {i32, i16, i16, [8 x i8]}
   layout if a definition of struct _GUID is not available. This is not
   ideal: in principle the two layouts could have different padding.

Reviewers: rnk, jdoerfert

Subscribers: arphaman, cfe-commits, aeubanks

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78171
2020-04-15 12:20:42 -07:00
Haojian Wu 17198dfaff [AST] Fix recovery-expr crash on invalid aligned attr.
Summary:
crash stack:

```
lang: tools/clang/include/clang/AST/AttrImpl.inc:1490: unsigned int clang::AlignedAttr::getAlignment(clang::ASTContext &) const: Assertion `!isAlignmentDependent()' failed.
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: ./bin/clang -cc1 -std=c++1y -ast-dump -frecovery-ast -fcxx-exceptions /tmp/t4.cpp
1.      /tmp/t4.cpp:3:31: current parser token ';'
 #0 0x0000000002530cff llvm::sys::PrintStackTrace(llvm::raw_ostream&) llvm-project/llvm/lib/Support/Unix/Signals.inc:564:13
 #1 0x000000000252ee30 llvm::sys::RunSignalHandlers() llvm-project/llvm/lib/Support/Signals.cpp:69:18
 #2 0x000000000253126c SignalHandler(int) llvm-project/llvm/lib/Support/Unix/Signals.inc:396:3
 #3 0x00007f86964d0520 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x13520)
 #4 0x00007f8695f9ff61 raise /build/glibc-oCLvUT/glibc-2.29/signal/../sysdeps/unix/sysv/linux/raise.c:51:1
 #5 0x00007f8695f8b535 abort /build/glibc-oCLvUT/glibc-2.29/stdlib/abort.c:81:7
 #6 0x00007f8695f8b40f _nl_load_domain /build/glibc-oCLvUT/glibc-2.29/intl/loadmsgcat.c:1177:9
 #7 0x00007f8695f98b92 (/lib/x86_64-linux-gnu/libc.so.6+0x32b92)
 #8 0x0000000004503d9f llvm::APInt::getZExtValue() const llvm-project/llvm/include/llvm/ADT/APInt.h:1623:5
 #9 0x0000000004503d9f clang::AlignedAttr::getAlignment(clang::ASTContext&) const llvm-project/build/tools/clang/include/clang/AST/AttrImpl.inc:1492:0
```

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78085
2020-04-15 16:15:20 +02:00
Haojian Wu 9657385960 [AST] Dont invalide VarDecl even the default initializaiton is failed.
Summary:
This patch would cause clang emit more diagnostics, but it is much better than https://reviews.llvm.org/D76831

```cpp
struct A {
  A(int);
  ~A() = delete;
};
void k() {
  A a;
}

```

before the patch:

/tmp/t3.cpp:24:5: error: no matching constructor for initialization of 'A'
  A a;
    ^
/tmp/t3.cpp:20:3: note: candidate constructor not viable: requires 1 argument, but 0 were provided
  A(int);
  ^
/tmp/t3.cpp:19:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 0 were provided
struct A {

After the patch:

/tmp/t3.cpp:24:5: error: no matching constructor for initialization of 'A'
  A a;
    ^
/tmp/t3.cpp:20:3: note: candidate constructor not viable: requires 1 argument, but 0 were provided
  A(int);
  ^
/tmp/t3.cpp:19:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 0 were provided
struct A {
       ^
/tmp/t3.cpp:24:5: error: attempt to use a deleted function
  A a;
    ^
/tmp/t3.cpp:21:3: note: '~A' has been explicitly marked deleted here
  ~A() = delete;

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77395
2020-04-14 12:58:48 +02:00
Reid Kleckner 55efb68c19 [MS] Mark vbase dtors used when marking dtor used
In the MS C++ ABI, the complete destructor variant for a class with
virtual bases is emitted whereever it is needed, instead of directly
alongside the base destructor variant. The complete destructor calls the
base destructor of the current class and the base destructors of each
virtual base. In order for this to work reliably, translation units that
use the destructor of a class also need to mark destructors of virtual
bases of that class used.

Fixes PR38521

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D77081
2020-04-09 14:19:36 -07:00
Haojian Wu 041080c247 [AST] Fix a crash on invalid constexpr Ctorinitializer when building RecoveryExpr.
Summary:
crash stack:

```

lang:  workspace/llvm-project/clang/lib/AST/ExprConstant.cpp:13704: bool EvaluateInPlace(clang::APValue &, (anonymous namespace)::EvalInfo &, const (anonymous namespace)::LValue &, const clang::Expr *, bool): Assertion `!E->isValueDependent()' failed.
 #8  EvaluateInPlace(clang::APValue&, (anonymous namespace)::EvalInfo&, (anonymous namespace)::LValue const&, clang::Expr const*, bool)  workspace/llvm-project/clang/lib/AST/ExprConstant.cpp:0:0
 #9  HandleConstructorCall(clang::Expr const*, (anonymous namespace)::LValue const&, clang::APValue*, clang::CXXConstructorDecl const*, (anonymous namespace)::EvalInfo&, clang::APValue&)  workspace/llvm-project/clang/lib/AST/ExprConstant.cpp:5779:57
#10  HandleConstructorCall(clang::Expr const*, (anonymous namespace)::LValue const&, llvm::ArrayRef<clang::Expr const*>, clang::CXXConstructorDecl const*, (anonymous namespace)::EvalInfo&, clang::APValue&)  workspace/llvm-project/clang/lib/AST/ExprConstant.cpp:5819:10
#11  clang::Expr::isPotentialConstantExpr(clang::FunctionDecl const*, llvm::SmallVectorImpl<std::pair<clang::SourceLocation, clang::PartialDiagnostic> >&) workspace/llvm-project/clang/lib/AST/ExprConstant.cpp:14746:5
#12  CheckConstexprFunctionBody(clang::Sema&, clang::FunctionDecl const*, clang::Stmt*, clang::Sema::CheckConstexprKind)  workspace/llvm-project/clang/lib/Sema/SemaDeclCXX.cpp:2306:7
#13  clang::Sema::CheckConstexprFunctionDefinition(clang::FunctionDecl const*, clang::Sema::CheckConstexprKind)  workspace/llvm-project/clang/lib/Sema/SemaDeclCXX.cpp:1766:0
#14  clang::Sema::ActOnFinishFunctionBody(clang::Decl*, clang::Stmt*, bool)  workspace/llvm-project/clang/lib/Sema/SemaDecl.cpp:14357:9
#15  clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&)  workspace/llvm-project/clang/lib/Parse/ParseStmt.cpp:2213:18
```

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: rsmith, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77041
2020-04-07 14:29:38 +02:00
Richard Smith c56975e299 Fix template instantiation of a non-dependent call to an inherited
constructor with default arguments.

We used to try to rebuild the call as a call to the faked-up inherited
constructor, which is only a placeholder and lacks (for example) default
arguments. Instead, build the call by reference to the original
constructor.

In passing, add a note to say where a call that recursively uses a
default argument from within itself occurs. This is usually pretty
obvious, but still at least somewhat useful, and would have saved
significant debugging time for this particular bug.
2020-04-06 19:20:30 -07:00
Richard Smith 944db8a433 Permit constant evaluation of mixed __builtin_memcmp between char and
char8_t.
2020-04-05 15:35:32 -07:00
Richard Smith 7f24db0175 Add documentation and testing for
2c88a485c7.

Also extend it to cover memchr for consistency.
2020-04-05 15:24:49 -07:00
Richard Smith 179f4baba0 Don't treat a CXXScopeSpec with a nested name specifier but no location
as invalid.

We create those when forming trivial type source information with no
associated location, which, unfortunately, we do create in some cases
(when a TreeTransform with no base location is used to transform a
QualType).

This would previously lead to rejects-valid bugs when we misinterpreted
these constructs as having no nested-name-specifier.
2020-04-03 20:20:48 -07:00
Richard Smith 4ede887992 PR45402: Make the restrictions on constant evaluation of memcmp and
memchr consistent and comprehensible, and document them.

We previously allowed evaluation of memcmp on arrays of integers of any
size, so long as the call evaluated to 0, and allowed evaluation of
memchr on any array of integral type of size 1 (including enums). The
purpose of constant-evaluating these builtins is only to support
constexpr std::char_traits, so we now consistently allow them on arrays
of (possibly signed or unsigned) char only.
2020-04-03 18:26:14 -07:00
Sam McCall 88fbadd0f5 [AST] clang::VectorType supports any size (that fits in unsigned)
Summary:
This matches llvm::VectorType.
It moves the size from the type bitfield into VectorType, increasing size by 8
bytes (including padding of 4). This is OK as we don't expect to create terribly
many of these types.

c.f. D77313 which enables large power-of-two sizes without growing VectorType.

Reviewers: efriedma, hokein

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77335
2020-04-03 17:30:31 +02:00
Weverything f93aed66f2 Fix diagnostics where _Atomic can't be applied
adb290d974 added a new case to
err_atomic_specifier_bad_type.  The diagnostic has two %select's
controlled by the same argument, but only the first was updated to have
the new case.  Add the extra case for the second %select and add a
test case that exercises the last case.
2020-03-31 17:23:35 -07:00
Eli Friedman 24485aec47 [clang analysis] Make mutex guard detection more reliable.
-Wthread-safety was failing to detect certain AST patterns it should
detect. Make the pattern detection a bit more comprehensive.

Due to an unrelated bug involving template instantiation, this showed up
as a regression in 10.0 vs. 9.0 in the original bug report. The included
testcase fails on older versions of clang, though.

Fixes https://bugs.llvm.org/show_bug.cgi?id=45323 .

Differential Revision: https://reviews.llvm.org/D76943
2020-03-30 11:46:02 -07:00
Richard Smith 9a7eda1bec PR45350: Handle unsized array CXXConstructExprs in constant evaluation
of array new expressions with runtime bound.
2020-03-29 19:33:56 -07:00
Richard Smith a5458bb0d6 Don't claim template names that name non-templates are undeclared. 2020-03-29 13:15:30 -07:00
Joerg Sonnenberger 09d4021853 Fix compatibility for __builtin_stdarg_start
The __builtin_stdarg_start is the legacy spelling of __builtin_va_start.
It should behave exactly the same, but for the last 9 years it would
behave subtly different for diagnostics. Follow the change from
29ad95b232 to require custom type checking.
2020-03-28 23:24:13 +01:00
Richard Smith 499b2a8d63 PR45294: Fix handling of assumed template names looked up in the lexical
scope.

There are a few contexts in which we assume a name is a template name;
if such a context is one where we should perform an unqualified lookup,
and lookup finds nothing, we would form a dependent template name even
if the name is not dependent. This happens in particular for the lookup
of a pseudo-destructor.

In passing, rename ActOnDependentTemplateName to just ActOnTemplateName
given that we apply it for non-dependent template names too.
2020-03-27 21:07:06 -07:00
Richard Smith 88c7ffaf94 Form invalid template-id annotations when parsing a construct that is
required to be a template-id but names an undeclared identifier.
2020-03-27 20:27:42 -07:00
Richard Smith 0c42539df3 Improve error recovery from missing '>' in template argument list.
Produce the conventional "to match this '<'" note, so that the user
knows why we expected a '>', and properly handle '>>' in C++11 onwards.
2020-03-27 18:59:01 -07:00
Richard Smith b3f6e3d6d6 Improve recovery from invalid template-ids.
Instead of bailing out of parsing when we encounter an invalid
template-name or template arguments in a template-id, produce an
annotation token describing the invalid construct.

This avoids duplicate errors and generally allows us to recover better.
In principle we should be able to extend this to store some kinds of
invalid template-id in the AST for tooling use, but that isn't handled
as part of this change.
2020-03-27 17:11:04 -07:00
Richard Sandiford c6824883cc [AST][SVE] Treat built-in SVE types as trivial
Built-in SVE types are trivial, since they're trivially copyable
and support default construction.

Differential Revision: https://reviews.llvm.org/D76692
2020-03-27 17:34:04 +00:00
Richard Sandiford 35392660e6 [AST][SVE] Treat built-in SVE types as trivially copyable
SVE types are trivially copyable: they can be copied simply
by reproducing the byte representation of the source object.

Differential Revision: https://reviews.llvm.org/D76691
2020-03-27 17:32:55 +00:00
Richard Sandiford 9dcb20a7d0 [AST][SVE] Treat built-in SVE types as POD
Built-in SVE types are POD in much the same that scalars and
fixed-length vectors are.

Differential Revision: https://reviews.llvm.org/D76690
2020-03-27 17:04:07 +00:00
Haojian Wu 62dea6e9be Revert "[AST] Build recovery expressions by default for C++."
This reverts commit 0788acbccb.
This reverts commit c2d7a1f79cedfc9fcb518596aa839da4de0adb69:  Revert "[clangd] Add test for FindTarget+RecoveryExpr (which already works). NFC"

It causes a crash on invalid code:

class X {
  decltype(unresolved()) foo;
};
constexpr int s = sizeof(X);
2020-03-26 16:25:32 +01:00
Haojian Wu a9ab11d408 [AST] Build recovery expressions for nonexistent member exprs.
Summary: Previously, we dropped the AST node for nonexistent member exprs.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76764
2020-03-26 08:50:33 +01:00
Erich Keane 044c51d8d4 Fix vector type scalar checking when the scalar operand is dependent
As reported in PR45298 and PR45299, vector_size type checking would
crash when done in a situation where the scalar is dependent, such as
a member of the current instantiation.

This is because the scalar checking ensures that you can implicitly
convert a value to a vector-type as long as it doesn't require
truncation. It does this by using the constant evaluator to get the
value as a float. Unfortunately, if the scalar is dependent (such as a
member of the current instantiation), we would hit the assert in the
evaluator.

This patch suppresses the truncation- of-value check in the first phase
of translation. All values are properly errored upon instantiation. This
has one minor regression, in that previously in a non-asserts build,

template<typename T>
struct S {
  float4 f(float4 f) {
    return k + f;
  }
  static constexpr k = 1.1; // causes a truncation on conversion.
};

would error immediately. Because 'k' is value dependent (as a
member-of-the-current-instantiation), this would still be evaluatable
(despite normally asserting).  Due to this patch, this diagnostic is
delayed until instantiation time.
2020-03-25 11:38:58 -07:00
Haojian Wu 0788acbccb [AST] Build recovery expressions by default for C++.
Update the existing tests.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76696
2020-03-25 09:00:48 +01:00
Momchil Velikov 080d046c91 [ARM][CMSE] Implement CMSE attributes
This patch adds CMSE attributes `cmse_nonsecure_call` and
`cmse_nonsecure_entry`.  As usual, specification is available here:
https://developer.arm.com/docs/ecm0359818/latest

Patch by Javed Absar, Bradley Smith, David Green, Momchil Velikov,
possibly others.

Differential Revision: https://reviews.llvm.org/D71129
2020-03-24 10:21:26 +00:00
Richard Smith 502915c619 PR45142: 'template ~X<T>' is ill-formed; reject it rather than crashing. 2020-03-23 15:07:06 -07:00
Tyker 180581cfcf [clang] Add support for consteval constructors
Summary:
Changes:
 - handle immediate invocations for constructors.
 - add tests

after this patch i believe the implementation of consteval is nearly standard compliant, but IR-gen still needs to be taught not to emit consteval declarations.

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: wchilders

Differential Revision: https://reviews.llvm.org/D74007
2020-03-20 11:33:54 +01:00
Richard Smith e7a811b319 PR45133: Don't crash if the active member of a union changes while it's
in the process of being initialized.
2020-03-17 20:37:14 -07:00
Richard Sandiford 4ece6f051b [Sema][SVE] Reject "delete" with sizeless types
Sizeless types can't be used with "new", so it doesn't make sense
to use them with "delete" either.  The SVE ACLE therefore doesn't
allow that.

This is slightly stronger than for normal incomplete types, since:

  struct S;
  void f(S *s) { delete s; }

is (by necessity) just a default-on warning rather than an error.

Differential Revision: https://reviews.llvm.org/D76219
2020-03-17 12:45:00 +00:00
Richard Sandiford 506406c4d5 [Sema][SVE] Reject "new" with sizeless types
new-expressions for a type T require sizeof(T) to be computable,
so the SVE ACLE does not allow them for sizeless types.  At the moment:

  auto f() { return new __SVInt8_t; }

creates a call to operator new with a zero size:

  %call = call noalias nonnull i8* @_Znwm(i64 0)

This patch reports an appropriate error instead.

Differential Revision: https://reviews.llvm.org/D76218
2020-03-17 12:23:46 +00:00
Richard Sandiford 72ffb16b4c [Sema][SVE] Don't allow sizeless types to be caught
In the current SVE ACLE spec, the usual rules for throwing and
catching incomplete types also apply to sizeless types.  However,
throwing pointers to sizeless types should not pose any real difficulty,
so as an extension, the clang implementation allows that.

This patch enforces these rules for catch statements.

Differential Revision: https://reviews.llvm.org/D76090
2020-03-17 12:00:16 +00:00
Richard Sandiford c47f971694 [Sema][SVE] Don't allow sizeless objects to be thrown
Summary:
The same rules for throwing and catching incomplete types also apply
to sizeless types.  This patch enforces that for throw statements.
It also make sure that we use "sizeless type" rather "incomplete type"
in the associated message.  (Both are correct, but "sizeless type" is
more specific and hopefully more user-friendly.)

The SVE ACLE simply extends the rule for incomplete types to
sizeless types.  However, throwing pointers to sizeless types
should not pose any real difficulty, so as an extension,
the clang implementation allows that.

Reviewers: sdesmalen, efriedma, rovka, rjmccall

Subscribers: tschuett, rkruppe, psnobl, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76088
2020-03-17 11:52:37 +00:00
Richard Sandiford 0947296902 [Sema][SVE] Reject sizeless types in exception specs
In the current SVE ACLE spec, the usual rules for throwing and
catching incomplete types also apply to sizeless types.  However,
throwing pointers to sizeless types should not pose any real difficulty,
so as an extension, the clang implementation allows that.

This patch enforces these rules for explicit exception specs.

Differential Revision: https://reviews.llvm.org/D76087
2020-03-17 11:39:03 +00:00
Richard Sandiford 94489f35a7 [Sema][SVE] Reject arithmetic on pointers to sizeless types
This patch completes a trio of changes related to arrays of
sizeless types.  It rejects various forms of arithmetic on
pointers to sizeless types, in the same way as for other
incomplete types.

Differential Revision: https://reviews.llvm.org/D76086
2020-03-17 11:35:20 +00:00
Richard Sandiford 010005f077 [Sema][SVE] Reject subscripts on pointers to sizeless types
clang currently accepts:

  __SVInt8_t &foo1(__SVInt8_t *x) { return *x; }
  __SVInt8_t &foo2(__SVInt8_t *x) { return x[1]; }

The first function is valid ACLE code and generates correct LLVM IR
(and assembly code).  But the second function is invalid for the
same reason that arrays of sizeless types are.  Trying to code-generate
the function leads to:

  llvm/include/llvm/Support/TypeSize.h:126: uint64_t llvm::TypeSize::getFixedSize() const: Assertion `!IsScalable && "Request for a fixed size on a s
calable object"' failed.

Another problem is that:

  template<typename T>
  constexpr __SIZE_TYPE__ f(T *x) { return &x[1] - x; }
  typedef int arr1[f((int *)0) - 1];
  typedef int arr2[f((__SVInt8_t *)0) - 1];

produces:

  a.cpp:2:48: warning: subtraction of pointers to type '__SVInt8_t' of zero size has undefined behavior [-Wpointer-arith]
  constexpr __SIZE_TYPE__ f(T *x) { return &x[1] - x; }
					   ~~~~~ ^ ~
  a.cpp:4:18: note: in instantiation of function template specialization 'f<__SVInt8_t>' requested here
  typedef int arr2[f((__SVInt8_t *)0) - 1];

This patch reports an appropriate diagnostic instead.

Differential Revision: https://reviews.llvm.org/D76084
2020-03-17 11:24:57 +00:00
Saar Raz 19fccc52ff [Concepts] Fix incorrect control flow when TryAnnotateTypeConstraint annotates an invalid template-id
TryAnnotateTypeConstraint could annotate a template-id which doesn't end up being a type-constraint,
in which case control flow would incorrectly flow into ParseImplicitInt.

Reenter the loop in this case.
Enable relevant tests for C++20. This required disabling typo-correction during TryAnnotateTypeConstraint
and changing a test case which is broken due to a separate bug (will be reported and handled separately).
2020-03-17 01:49:42 +02:00
Aaron Ballman dab43c8592 Remove some explicit calls to getName() when printing diagnostics; NFC 2020-03-14 17:01:45 -04:00