clang drops `alignsas` on struct field

[ahatanak]

$ cat test.c

#include <assert.h>

struct S {
  alignas(16) char bytes[16];
};

static_assert(alignof(struct S) == 16);

$ clang -std=c2x test.c -c -o /dev/null

<source>:7:15: error: static assertion failed due to requirement '_Alignof(struct S) == 16'
    7 | static_assert(alignof(struct S) == 16);
      |               ^~~~~~~~~~~~~~~~~~~~~~~
<source>:7:33: note: expression evaluates to '1 == 16'
    7 | static_assert(alignof(struct S) == 16);
      |               ~~~~~~~~~~~~~~~~~~^~~~~
1 error generated.

[ahatanak]

Prior to b9cf7f1, alignof(struct S) was returning 16.

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Akira Hatanaka (ahatanak)

$ cat test.c ``` #include <assert.h>

struct S {
alignas(16) char bytes[16];
};

static_assert(alignof(struct S) == 16);

$ clang -std=c2x test.c -c -o /dev/null
<source>:7:15: error: static assertion failed due to requirement '_Alignof(struct S) == 16'
    7 | static_assert(alignof(struct S) == 16);
      |               ^~~~~~~~~~~~~~~~~~~~~~~
<source>:7:33: note: expression evaluates to '1 == 16'
    7 | static_assert(alignof(struct S) == 16);
      |               ~~~~~~~~~~~~~~~~~~^~~~~
1 error generated.
</details>

[ahatanak]

CC @AaronBallman

[ahatanak]

It looks like DS's attributes have to be moved to Attrs in Parser::ParseStructDeclaration after the call to ParseSpecifierQualifierList(DS).

[AaronBallman]

Oof, sorry about the regression -- you're correct, this seems to have broke with that commit.

[AaronBallman]

Yeah, the attribute is no longer on the AST node:

|-RecordDecl 0x218beb939b0 <C:\Users\aballman\OneDrive - Intel Corporation\Desktop\test.c:1:1, line:3:1> line:1:8 struct S definition
| `-FieldDecl 0x218beb93b20 <line:2:3, col:28> col:20 bytes 'char[16]'