[Bug binutils/32531] New: [GAS] Intel Assembly Bugs (Mishandle Directive Names)

[witbring at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=32531

            Bug ID: 32531
           Summary: [GAS] Intel Assembly Bugs (Mishandle Directive Names)
           Product: binutils
           Version: 2.38
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: binutils
          Assignee: unassigned at sourceware dot org
          Reporter: witbring at gmail dot com
  Target Milestone: ---

I am reporting GNU AS bug found during research.
The tests were conducted using the latest version (v2.38).
The issue occurs in the same way with previous versions as well.

When some directive names are used in memory operands, incorrect binary code is
generated.
It seems that the issue arises due to handling the data labels used in the mov
instruction as directives.`


1. Example Code

```
.intel_syntax noprefix
.data
byte:
word:
qword:
    .long 0

.text
test:
        mov     edx, DWORD PTR [byte]
        mov     edx, DWORD PTR [word]
        mov     edx, DWORD PTR [qword]
```

2. Compilation Command

```
gcc -c test.c
```

3. Compiled Binary Output
The memory operands were replaced with constant values in the compiled binary
code.

```
0000000000000000 <test>:
   0:   8b 14 25 01 00 00 00    mov    edx,DWORD PTR ds:0x1
   7:   8b 14 25 02 00 00 00    mov    edx,DWORD PTR ds:0x2
   e:   8b 14 25 02 00 00 00    mov    edx,DWORD PTR ds:0x4
```

This related bug can also be observed when we use other labels such as qword.
rd, qword, tbyte, owrd, xmmword, ymmword, zmmword, far, and near.


This bug can also be reproduced on Godbolt:
https://godbolt.org/z/hj49W734M

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