Author: rakete1111
Date: Sun May 19 08:07:58 2019
New Revision: 361119
URL: http://llvm.org/viewvc/llvm-project?rev=361119&view=rev
Log:
Added a better diagnostic when using the delete operator with lambdas
Summary:
This adds a new error for missing parentheses around lambdas in delete
operators.
```
int main() {
delete []() { return new int(); }();
}
```
This will result in:
```
test.cpp:2:3: error: '[]' after delete interpreted as 'delete[]'
delete []() { return new int(); }();
^~~~~~~~~
test.cpp:2:9: note: add parentheses around the lambda
delete []() { return new int(); }();
^
( )
```
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: riccibruno, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D36357
Modified:
cfe/trunk/include/clang/Basic/DiagnosticParseKinds.td
cfe/trunk/lib/Parse/ParseExprCXX.cpp
cfe/trunk/test/FixIt/fixit-cxx0x.cpp
cfe/trunk/test/Parser/cxx0x-lambda-expressions.cpp
cfe/trunk/test/SemaCXX/new-delete-0x.cpp
Modified: cfe/trunk/include/clang/Basic/DiagnosticParseKinds.td
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticParseKinds.td?rev=361119&r1=361118&r2=361119&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticParseKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticParseKinds.td Sun May 19 08:07:58
2019
@@ -109,6 +109,8 @@ def warn_cxx98_compat_alignof : Warning<
InGroup<CXX98Compat>, DefaultIgnore;
def ext_alignof_expr : ExtWarn<
"%0 applied to an expression is a GNU extension">,
InGroup<GNUAlignofExpression>;
+def err_lambda_after_delete : Error<
+ "'[]' after delete interpreted as 'delete[]'; add parentheses to treat this
as a lambda-expression">;
def warn_microsoft_dependent_exists : Warning<
"dependent %select{__if_not_exists|__if_exists}0 declarations are ignored">,
Modified: cfe/trunk/lib/Parse/ParseExprCXX.cpp
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Parse/ParseExprCXX.cpp?rev=361119&r1=361118&r2=361119&view=diff
==============================================================================
--- cfe/trunk/lib/Parse/ParseExprCXX.cpp (original)
+++ cfe/trunk/lib/Parse/ParseExprCXX.cpp Sun May 19 08:07:58 2019
@@ -3034,8 +3034,58 @@ Parser::ParseCXXDeleteExpression(bool Us
// [Footnote: A lambda expression with a lambda-introducer that consists
// of empty square brackets can follow the delete keyword if
// the lambda expression is enclosed in parentheses.]
- // FIXME: Produce a better diagnostic if the '[]' is unambiguously a
- // lambda-introducer.
+
+ const Token Next = GetLookAheadToken(2);
+
+ // Basic lookahead to check if we have a lambda expression.
+ if (Next.isOneOf(tok::l_brace, tok::less) ||
+ (Next.is(tok::l_paren) &&
+ (GetLookAheadToken(3).is(tok::r_paren) ||
+ (GetLookAheadToken(3).is(tok::identifier) &&
+ GetLookAheadToken(4).is(tok::identifier))))) {
+ TentativeParsingAction TPA(*this);
+ SourceLocation LSquareLoc = Tok.getLocation();
+ SourceLocation RSquareLoc = NextToken().getLocation();
+
+ // SkipUntil can't skip pairs of </*...*/>; don't emit a FixIt in this
+ // case.
+ SkipUntil({tok::l_brace, tok::less}, StopBeforeMatch);
+ SourceLocation RBraceLoc;
+ bool EmitFixIt = false;
+ if (TryConsumeToken(tok::l_brace)) {
+ SkipUntil(tok::r_brace, StopBeforeMatch);
+ RBraceLoc = Tok.getLocation();
+ EmitFixIt = true;
+ }
+
+ TPA.Revert();
+
+ if (EmitFixIt)
+ Diag(Start, diag::err_lambda_after_delete)
+ << SourceRange(Start, RSquareLoc)
+ << FixItHint::CreateInsertion(LSquareLoc, "(")
+ << FixItHint::CreateInsertion(
+ Lexer::getLocForEndOfToken(
+ RBraceLoc, 0, Actions.getSourceManager(),
getLangOpts()),
+ ")");
+ else
+ Diag(Start, diag::err_lambda_after_delete)
+ << SourceRange(Start, RSquareLoc);
+
+ // Warn that the non-capturing lambda isn't surrounded by parentheses
+ // to disambiguate it from 'delete[]'.
+ ExprResult Lambda = ParseLambdaExpression();
+ if (Lambda.isInvalid())
+ return ExprError();
+
+ // Evaluate any postfix expressions used on the lambda.
+ Lambda = ParsePostfixExpressionSuffix(Lambda);
+ if (Lambda.isInvalid())
+ return ExprError();
+ return Actions.ActOnCXXDelete(Start, UseGlobal, /*ArrayForm=*/false,
+ Lambda.get());
+ }
+
ArrayDelete = true;
BalancedDelimiterTracker T(*this, tok::l_square);
Modified: cfe/trunk/test/FixIt/fixit-cxx0x.cpp
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/test/FixIt/fixit-cxx0x.cpp?rev=361119&r1=361118&r2=361119&view=diff
==============================================================================
--- cfe/trunk/test/FixIt/fixit-cxx0x.cpp (original)
+++ cfe/trunk/test/FixIt/fixit-cxx0x.cpp Sun May 19 08:07:58 2019
@@ -58,6 +58,9 @@ void S2::f(int i) {
(void)[&, i, i]{ }; // expected-error{{'i' can appear only once in a capture
list}}
(void)[] mutable { }; // expected-error{{lambda requires '()' before
'mutable'}}
(void)[] -> int { }; // expected-error{{lambda requires '()' before return
type}}
+
+ delete []() { return new int; }(); // expected-error{{'[]' after delete
interpreted as 'delete[]'}}
+ delete [] { return new int; }(); // expected-error{{'[]' after delete
interpreted as 'delete[]'}}
}
#define bar "bar"
Modified: cfe/trunk/test/Parser/cxx0x-lambda-expressions.cpp
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Parser/cxx0x-lambda-expressions.cpp?rev=361119&r1=361118&r2=361119&view=diff
==============================================================================
--- cfe/trunk/test/Parser/cxx0x-lambda-expressions.cpp (original)
+++ cfe/trunk/test/Parser/cxx0x-lambda-expressions.cpp Sun May 19 08:07:58 2019
@@ -1,4 +1,5 @@
// RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify -std=c++11 %s
+// RUN: %clang_cc1 -fsyntax-only -Wno-unused-value -verify -std=c++2a %s
enum E { e };
@@ -43,31 +44,57 @@ class C {
int a4[1] = {[&b] = 1 }; // expected-error{{integral constant expression
must have integral or unscoped enumeration type, not 'const int *'}}
int a5[3] = { []{return 0;}() };
int a6[1] = {[this] = 1 }; // expected-error{{integral constant expression
must have integral or unscoped enumeration type, not 'C *'}}
- int a7[1] = {[d(0)] { return d; } ()}; // expected-warning{{extension}}
- int a8[1] = {[d = 0] { return d; } ()}; // expected-warning{{extension}}
+ int a7[1] = {[d(0)] { return d; } ()};
+ int a8[1] = {[d = 0] { return d; } ()};
+ int a10[1] = {[id(0)] { return id; } ()};
+#if __cplusplus <= 201103L
+ // expected-warning@-4{{extension}}
+ // expected-warning@-4{{extension}}
+ // expected-warning@-4{{extension}}
+#endif
int a9[1] = {[d = 0] = 1}; // expected-error{{is not an integral constant
expression}}
- int a10[1] = {[id(0)] { return id; } ()}; // expected-warning{{extension}}
+#if __cplusplus >= 201402L
+ // expected-note@-2{{constant expression cannot modify an object that is
visible outside that expression}}
+#endif
int a11[1] = {[id(0)] = 1};
}
void delete_lambda(int *p) {
delete [] p;
delete [] (int*) { new int }; // ok, compound-literal, not lambda
- delete [] { return new int; } (); // expected-error{{expected expression}}
+ delete [] { return new int; } (); // expected-error {{'[]' after delete
interpreted as 'delete[]'}}
delete [&] { return new int; } (); // ok, lambda
+
+ delete []() { return new int; }(); // expected-error{{'[]' after delete
interpreted as 'delete[]'}}
+ delete [](E Enum) { return new int((int)Enum); }(e); //
expected-error{{'[]' after delete interpreted as 'delete[]'}}
+#if __cplusplus > 201703L
+ delete []<int = 0>() { return new int; }(); // expected-error{{'[]' after
delete interpreted as 'delete[]'}}
+#endif
}
// We support init-captures in C++11 as an extension.
int z;
void init_capture() {
- [n(0)] () mutable -> int { return ++n; }; // expected-warning{{extension}}
- [n{0}] { return; }; // expected-warning{{extension}}
- [n = 0] { return ++n; }; // expected-error {{captured by copy in a
non-mutable}} expected-warning{{extension}}
- [n = {0}] { return; }; // expected-error {{<initializer_list>}}
expected-warning{{extension}}
- [a([&b = z]{})](){}; // expected-warning 2{{extension}}
+ [n(0)] () mutable -> int { return ++n; };
+ [n{0}] { return; };
+ [a([&b = z]{})](){};
+ [n = 0] { return ++n; }; // expected-error {{captured by copy in a
non-mutable}}
+ [n = {0}] { return; }; // expected-error {{<initializer_list>}}
+#if __cplusplus <= 201103L
+ // expected-warning@-6{{extension}}
+ // expected-warning@-6{{extension}}
+ // expected-warning@-6{{extension}}
+ // expected-warning@-7{{extension}}
+ // expected-warning@-7{{extension}}
+ // expected-warning@-7{{extension}}
+#endif
int x = 4;
- auto y = [&r = x, x = x + 1]() -> int { // expected-warning 2{{extension}}
+ auto y = [&r = x, x = x + 1]() -> int {
+#if __cplusplus <= 201103L
+ // expected-warning@-2{{extension}}
+ // expected-warning@-3{{extension}}
+#endif
r += 2;
return x + 2;
} ();
Modified: cfe/trunk/test/SemaCXX/new-delete-0x.cpp
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/new-delete-0x.cpp?rev=361119&r1=361118&r2=361119&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/new-delete-0x.cpp (original)
+++ cfe/trunk/test/SemaCXX/new-delete-0x.cpp Sun May 19 08:07:58 2019
@@ -34,6 +34,5 @@ void good_deletes()
void bad_deletes()
{
// 'delete []' is always array delete, per [expr.delete]p1.
- // FIXME: Give a better diagnostic.
- delete []{ return (int*)0; }(); // expected-error {{expected expression}}
+ delete []{ return (int*)0; }(); // expected-error {{'[]' after delete
interpreted as 'delete[]'}}
}
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