[Bug c/128507] New: asm att syntax error: movzww (%rax),%ax

[romph at gmx dot net via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=128507

            Bug ID: 128507
           Summary: asm att syntax error: movzww (%rax),%ax
           Product: gcc
           Version: 15.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: romph at gmx dot net
  Target Milestone: ---

The asm(...) command in att syntax:
"movzww (%rax),%ax;"
generates the error
Error: invalid instruction suffix for `movzw'
The intel syntax version works without errors.

asm
(
 ".intel_syntax noprefix;"
 "movzx  ax,WORD PTR [rax];"
 "movzx  eax,WORD PTR [rax];"
 "movzx  rax,WORD PTR [rax];"

 ".att_syntax noprefix;"
 // Error: invalid instruction suffix for `movzw'
 //"movzww (%rax),%ax;"
 "movzwl (%rax),%eax;"
 "movzwq (%rax),%rax;"
 );