[gcc r12-5867] Leverage VX_CPU_PREFIX in aarch64-vxworks.h

[Olivier Hainque <hainque@gcc.gnu.org>]

https://gcc.gnu.org/g:1486e4bd015423a70eb6fad1f42cb0a381967022

commit r12-5867-g1486e4bd015423a70eb6fad1f42cb0a381967022
Author: Olivier Hainque <hainque@adacore.com>
Date:   Fri Apr 9 15:46:42 2021 +0000

    Leverage VX_CPU_PREFIX in aarch64-vxworks.h
    
    This change tightens the CPU macro definitions issued
    for VxWorks system headers on aarch64 to incorporate
    the common VX_CPU_PREFIX facility, as the powerpc port
    does.
    
    The net effect for current configurations is the addition
    of an actual "_VX_" prefix to the references to architecture
    representative values. The absence of this prefix is most
    often compensated for in system headers, but not always (when
    going through particular #include paths), and this caused
    a couple of spurious test failures.
    
    2021-12-09  Olivier Hainque  <hainque@adacore.com>
    
    gcc/
            * config/aarch64/aarch64-vxworks.h (TARGET_OS_CPP_BUILTINS):
            Use VX_CPU_PREFIX in CPU definitions.

Diff:
---
 gcc/config/aarch64/aarch64-vxworks.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gcc/config/aarch64/aarch64-vxworks.h b/gcc/config/aarch64/aarch64-vxworks.h
index d5bdb4efb61..a821bdef2eb 100644
--- a/gcc/config/aarch64/aarch64-vxworks.h
+++ b/gcc/config/aarch64/aarch64-vxworks.h
@@ -50,7 +50,8 @@ along with GCC; see the file COPYING3.  If not see
       builtin_define ("ARMEB");                 \
     else                                        \
       builtin_define ("ARMEL");                 \
-    builtin_define ("_VX_CPU=ARMARCH8A"); \
+    builtin_define \
+      (VX_CPU_PREFIX "CPU=" VX_CPU_PREFIX "ARMARCH8A");	\
     VXWORKS_OS_CPP_BUILTINS ();		  \
   } while (0)