14 Commits

Author SHA1 Message Date
yronglin
3cfdef3715
[Clang] Fix the for statement disappearing in AST when an error occurs in the conditional expression of the for statement (#65381)
Consider:
```
constexpr int f() {
    int sum = 0;
    for (int i = 0; undefined_var; ++i) {
        sum += i;
    }
    return sum;
}

static_assert(f());
```

The AST before this patch:
```
|-FunctionDecl <line:1:1, line:7:1> line:1:15 used constexpr f 'int ()' implicit-inline
| `-CompoundStmt <col:19, line:7:1>
|   |-DeclStmt <line:2:5, col:16>
|   | `-VarDecl <col:5, col:15> col:9 used sum 'int' cinit
|   |   `-IntegerLiteral <col:15> 'int' 0
|   `-ReturnStmt <line:6:5, col:12>
|     `-ImplicitCastExpr <col:12> 'int' <LValueToRValue>
|       `-DeclRefExpr <col:12> 'int' lvalue Var 0xb870518 'sum' 'int'
```

The AST after this patch:
```
|-FunctionDecl 0x11d0f63f8 <./main.cpp:1:1, line:7:1> line:1:15 used constexpr f 'int ()' implicit-inline
| `-CompoundStmt 0x11d110880 <col:19, line:7:1>
|   |-DeclStmt 0x11d0f65c8 <line:2:5, col:16>
|   | `-VarDecl 0x11d0f6528 <col:5, col:15> col:9 used sum 'int' cinit
|   |   `-IntegerLiteral 0x11d0f6590 <col:15> 'int' 0
|   |-ForStmt 0x11d110800 <line:3:5, line:5:5>
|   | |-DeclStmt 0x11d0f66a0 <line:3:10, col:19>
|   | | `-VarDecl 0x11d0f6600 <col:10, col:18> col:14 used i 'int' cinit
|   | |   `-IntegerLiteral 0x11d0f6668 <col:18> 'int' 0
|   | |-<<<NULL>>>
|   | |-RecoveryExpr 0x11d0f66e8 <col:21> 'bool' contains-errors
|   | |-UnaryOperator 0x11d0f6728 <col:36, col:38> 'int' lvalue prefix '++'
|   | | `-DeclRefExpr 0x11d0f6708 <col:38> 'int' lvalue Var 0x11d0f6600 'i' 'int'
|   | `-CompoundStmt 0x11d0f67c8 <col:41, line:5:5>
|   |   `-CompoundAssignOperator 0x11d0f6798 <line:4:9, col:16> 'int' lvalue '+=' ComputeLHSTy='int' ComputeResultTy='int'
|   |     |-DeclRefExpr 0x11d0f6740 <col:9> 'int' lvalue Var 0x11d0f6528 'sum' 'int'
|   |     `-ImplicitCastExpr 0x11d0f6780 <col:16> 'int' <LValueToRValue>
|   |       `-DeclRefExpr 0x11d0f6760 <col:16> 'int' lvalue Var 0x11d0f6600 'i' 'int'
|   `-ReturnStmt 0x11d110870 <line:6:5, col:12>
|     `-ImplicitCastExpr 0x11d110858 <col:12> 'int' <LValueToRValue>
|       `-DeclRefExpr 0x11d110838 <col:12> 'int' lvalue Var 0x11d0f6528 'sum' 'int'
```

---------

Co-authored-by: Shafik Yaghmour <shafik@users.noreply.github.com>
2023-09-09 00:48:06 +08:00
yronglin
111c1ba5b4
[NFC][Clang] Fix test constexpr-function-recovery-crash.cpp (#65269)
Signed-off-by: yronglin <yronglin777@gmail.com>
2023-09-05 23:21:44 +08:00
yrong
a2132d72be [Clang] Fix the do while statement disappearing in AST when an error occurs in the conditional expression of the do while statement
```
constexpr int test() {
    do {} while (a + 1 < 10);
    return 0;
}
```
Before:
```
`-FunctionDecl 0x56512a172650 <./recovery.cpp:1:1, line:4:1> line:1:15 constexpr test 'int ()' implicit-inline
  `-CompoundStmt 0x56512a172860 <col:22, line:4:1>
    `-ReturnStmt 0x56512a172850 <line:3:5, col:12>
      `-IntegerLiteral 0x56512a172830 <col:12> 'int' 0
```
Now:
```
`-FunctionDecl 0x5642c4804650 <./recovery.cpp:1:1, line:4:1> line:1:15 constexpr test 'int ()' implicit-inline
  `-CompoundStmt 0x5642c48048e0 <col:22, line:4:1>
    |-DoStmt 0x5642c4804890 <line:2:5, col:28>
    | |-CompoundStmt 0x5642c4804740 <col:8, col:9>
    | `-BinaryOperator 0x5642c4804870 <col:18, col:26> '<dependent type>' contains-errors '<'
    |   |-BinaryOperator 0x5642c4804850 <col:18, col:22> '<dependent type>' contains-errors '+'
    |   | |-RecoveryExpr 0x5642c4804830 <col:18> '<dependent type>' contains-errors lvalue
    |   | `-IntegerLiteral 0x5642c48047b0 <col:22> 'int' 1
    |   `-IntegerLiteral 0x5642c48047f0 <col:26> 'int' 10
    `-ReturnStmt 0x5642c48048d0 <line:3:5, col:12>
      `-IntegerLiteral 0x5642c48048b0 <col:12> 'int' 0
```

Reviewed By: hokein

Differential Revision: https://reviews.llvm.org/D157195
2023-08-08 19:34:43 +08:00
yronglin
36f67434f7 [AST] Stop evaluate constant expression if the condition expression which in switch statement contains errors
This fix issue: https://github.com/llvm/llvm-project/issues/63453

```
constexpr int foo(unsigned char c) {
    switch (f) {
    case 0:
        return 7;
    default:
        break;
    }
    return 0;
}

static_assert(foo('d'));

```

Reviewed By: aaron.ballman, erichkeane, hokein

Differential Revision: https://reviews.llvm.org/D153296
2023-07-07 19:56:47 +08:00
Muhammad Usman Shahid
76476efd68 Rewording "static_assert" diagnostics
This patch rewords the static assert diagnostic output. Failing a
_Static_assert in C should not report that static_assert failed. This
changes the wording to be more like GCC and uses "static assertion"
when possible instead of hard coding the name. This also changes some
instances of 'static_assert' to instead be based on the token in the
source code.

Differential Revision: https://reviews.llvm.org/D129048
2022-07-25 07:22:54 -04:00
Erich Keane
1da3119025 Revert "Rewording the "static_assert" to static assertion"
Looks like we again are going to have problems with libcxx tests that
are overly specific in their dependency on clang's diagnostics.

This reverts commit 6542cb55a3eb115b1c3592514590a19987ffc498.
2022-07-21 06:40:14 -07:00
Muhammad Usman Shahid
6542cb55a3 Rewording the "static_assert" to static assertion
This patch is basically the rewording of the static assert statement's
output(error) on screen after failing. Failing a _Static_assert in C
should not report that static_assert failed. It’d probably be better to
reword the diagnostic to be more like GCC and say “static assertion”
failed in both C and C++.

consider a c file having code

_Static_assert(0, "oh no!");

In clang the output is like:

<source>:1:1: error: static_assert failed: oh no!
_Static_assert(0, "oh no!");
^              ~
1 error generated.
Compiler returned: 1

Thus here the "static_assert" is not much good, it will be better to
reword it to the "static assertion failed" to more generic. as the gcc
prints as:

<source>:1:1: error: static assertion failed: "oh no!"
    1 | _Static_assert(0, "oh no!");
          | ^~~~~~~~~~~~~~
          Compiler returned: 1

The above can also be seen here. This patch is about rewording
the static_assert to static assertion.

Differential Revision: https://reviews.llvm.org/D129048
2022-07-21 06:34:14 -07:00
Mitch Phillips
041d4012e4 Revert "Rewording "static_assert" diagnostics"
This reverts commit b7e77ff25fb2412f6ab6d6cc756666b0e2f97bd3.

Reason: Broke sanitizer builds bots + libcxx. 'static assertion
expression is not an integral constant expression'. More details
available in the Phabricator review: https://reviews.llvm.org/D129048
2022-07-14 10:59:20 -07:00
Muhammad Usman Shahid
b7e77ff25f Rewording "static_assert" diagnostics
This patch rewords the static assert diagnostic output. Failing a
_Static_assert in C should not report that static_assert failed. This
changes the wording to be more like GCC and uses "static assertion"
when possible instead of hard coding the name. This also changes some
instances of 'static_assert' to instead be based on the token in the
source code.

Differential Revision: https://reviews.llvm.org/D129048
2022-07-14 07:47:37 -04:00
Sam McCall
27ea0c4e72 [Parse] Use empty RecoveryExpr when if/while/do/switch conditions fail to parse
This allows the body to be parsed.
An special-case that would replace a missing if condition with OpaqueValueExpr
was removed as it's now redundant (unless recovery-expr is disabled).

For loops are not handled at this point, as the parsing is more complicated.

Differential Revision: https://reviews.llvm.org/D113752
2022-01-10 10:38:27 +01:00
Sam McCall
71059f26d3 [AST] Produce ReturnStmt containing RecoveryExpr when type is wrong
Previously we just drop the ReturnStmt and its argument from the AST,
which blocks analysis of broken code.

Fixes https://github.com/llvm/llvm-project/issues/39944

Differential Revision: https://reviews.llvm.org/D116414
2022-01-04 17:07:55 +01:00
Sam McCall
de7494a33a [AST] fail rather than crash when const evaluating invalid c++ foreach
Differential Revision: https://reviews.llvm.org/D112633
2021-10-27 22:45:32 +02:00
Haojian Wu
a053929854 [AST] Fix a constexpr-evaluator crash on error-dependent returnstmt.
When the evaluator encounters an error-dependent returnstmt, before this patch
it returned a ESR_Returned without setting the result, the callsides think this
is a successful execution, and try to access the Result which causes the crash.

The fix is to always return failed as we don't know the result of the
error-dependent return stmt.

Differential Revision: https://reviews.llvm.org/D92969
2020-12-10 10:12:15 +01:00
Haojian Wu
bd4662cd3f [AST] Enhance the const expression evaluator to support error-dependent exprs.
Fix a crash when evaluating a constexpr function which contains
recovery-exprs. https://bugs.llvm.org/show_bug.cgi?id=46837

Would be nice to have constant expression evaluator support general template
value-dependent expressions, but it requires more work.

This patch is a good start I think, to handle the error-only
value-dependent expressions.

Differential Revision: https://reviews.llvm.org/D84637
2020-11-18 15:48:06 +01:00