[gcc r14-6028] aarch64: Avoid -Wincompatible-pointer-types warning in Linux unwinder

[Florian Weimer]

https://gcc.gnu.org/g:335bd6c938c254e3ae4b019cfc8a94bb8009ca81

commit r14-6028-g335bd6c938c254e3ae4b019cfc8a94bb8009ca81
Author: Florian Weimer <fweimer@redhat.com>
Date:   Fri Dec 1 08:10:12 2023 +0100

    aarch64: Avoid -Wincompatible-pointer-types warning in Linux unwinder
    
            * config/aarch64/linux-unwind.h
            (aarch64_fallback_frame_state): Add cast to the expected type
            in sc assignment.

Diff:
---
 libgcc/config/aarch64/linux-unwind.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/libgcc/config/aarch64/linux-unwind.h b/libgcc/config/aarch64/linux-unwind.h
index 00eba866049..18b3df71e7b 100644
--- a/libgcc/config/aarch64/linux-unwind.h
+++ b/libgcc/config/aarch64/linux-unwind.h
@@ -77,7 +77,10 @@ aarch64_fallback_frame_state (struct _Unwind_Context *context,
     }
 
   rt_ = context->cfa;
-  sc = &rt_->uc.uc_mcontext;
+  /* Historically, the uc_mcontext member was of type struct sigcontext, but
+     glibc uses a different type now with member names in the implementation
+     namespace.  */
+  sc = (struct sigcontext *) &rt_->uc.uc_mcontext;
 
 /* This define duplicates the definition in aarch64.md */
 #define SP_REGNUM 31