[PATCH 0/1] MR4547: ntdll: Fix macOS build error with LLVM 17.

[Brendan Shanks (＠bshanks)]

Starting with LLVM 17, having non-private labels between `.cfi_startproc`/`.cfi_endproc` triggers "invalid CFI advance_loc expression" errors when targeting Mach-O.

Use local labels instead, and store the pointer in `.data` so it can be read by `handle_syscall_trap()`.

Based on a patch by Jacek Caban.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=55863

[PATCH 1/1] ntdll: Fix macOS build error with LLVM 17.

[Brendan Shanks]

From: Brendan Shanks

LLVM no longer allows non-private labels to appear between
.cfi_startproc/endproc when targeting Mach-O.

Based on a patch by Jacek Caban.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=55863
---
 dlls/ntdll/unix/signal_x86_64.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/dlls/ntdll/unix/signal_x86_64.c b/dlls/ntdll/unix/signal_x86_64.c
index 17a558da74c..8dd976fb987 100644
--- a/dlls/ntdll/unix/signal_x86_64.c
+++ b/dlls/ntdll/unix/signal_x86_64.c
@@ -1879,15 +1879,15 @@ static BOOL handle_syscall_trap( ucontext_t *sigcontext )

if ((void *)RIP_sig( sigcontext ) == __wine_syscall_dispatcher)
     {
-        extern void __wine_syscall_dispatcher_prolog_end(void);
+        extern const void *__wine_syscall_dispatcher_prolog_end_ptr;

-        RIP_sig( sigcontext ) = (ULONG64)__wine_syscall_dispatcher_prolog_end;
+        RIP_sig( sigcontext ) = (ULONG64)__wine_syscall_dispatcher_prolog_end_ptr;
     }
     else if ((void *)RIP_sig( sigcontext ) == __wine_unix_call_dispatcher)
     {
-        extern void __wine_unix_call_dispatcher_prolog_end(void);
+        extern const void *__wine_unix_call_dispatcher_prolog_end_ptr;

-        RIP_sig( sigcontext ) = (ULONG64)__wine_unix_call_dispatcher_prolog_end;
+        RIP_sig( sigcontext ) = (ULONG64)__wine_unix_call_dispatcher_prolog_end_ptr;
         R10_sig( sigcontext ) = RCX_sig( sigcontext );
     }
     else return FALSE;
@@ -2594,8 +2594,7 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
                    "popq 0x80(%rcx)\n\t"
                    __ASM_CFI(".cfi_adjust_cfa_offset -8\n\t")
                    "movl $0,0xb4(%rcx)\n\t"        /* frame->restore_flags */
-                   ".globl " __ASM_NAME("__wine_syscall_dispatcher_prolog_end") "\n"
-                   __ASM_NAME("__wine_syscall_dispatcher_prolog_end") ":\n\t"
+                   __ASM_LOCAL_LABEL("__wine_syscall_dispatcher_prolog_end") ":\n\t"
                    "movq %rax,0x00(%rcx)\n\t"
                    "movq %rbx,0x08(%rcx)\n\t"
                    __ASM_CFI_REG_IS_AT1(rbx, rcx, 0x08)
@@ -2831,8 +2830,7 @@ __ASM_GLOBAL_FUNC( __wine_unix_call_dispatcher,
                    __ASM_CFI(".cfi_adjust_cfa_offset -8\n\t")
                    __ASM_CFI_REG_IS_AT2(rip, rcx, 0xf0,0x00)
                    "movl $0,0xb4(%rcx)\n\t"        /* frame->restore_flags */
-                   ".globl " __ASM_NAME("__wine_unix_call_dispatcher_prolog_end") "\n"
-                   __ASM_NAME("__wine_unix_call_dispatcher_prolog_end") ":\n\t"
+                   __ASM_LOCAL_LABEL("__wine_unix_call_dispatcher_prolog_end") ":\n\t"
                    "movq %rbx,0x08(%rcx)\n\t"
                    __ASM_CFI_REG_IS_AT1(rbx, rcx, 0x08)
                    "movq %rsi,0x20(%rcx)\n\t"
@@ -2930,6 +2928,14 @@ __ASM_GLOBAL_FUNC( __wine_unix_call_dispatcher,
                    __ASM_CFI(".cfi_adjust_cfa_offset 8\n\t")
                    "ret" )

+asm( ".data\n\t"
+     ".globl " __ASM_NAME("__wine_syscall_dispatcher_prolog_end_ptr") "\n"
+     __ASM_NAME("__wine_syscall_dispatcher_prolog_end_ptr") ":\n\t"
+     ".8byte " __ASM_LOCAL_LABEL("__wine_syscall_dispatcher_prolog_end") "\n\t"
+     ".globl " __ASM_NAME("__wine_unix_call_dispatcher_prolog_end_ptr") "\n"
+     __ASM_NAME("__wine_unix_call_dispatcher_prolog_end_ptr") ":\n\t"
+     ".8byte " __ASM_LOCAL_LABEL("__wine_unix_call_dispatcher_prolog_end") "\n\t"
+     ".text\n\t" );

/***********************************************************************
  *           __wine_setjmpex