[PAC][libunwind] Fix gcc build of libunwind and compiler-rt (#164535)
This adds guards on the ptrauth feature checks so that they are only
performed if __has_feature is actually available.
GitOrigin-RevId: c1678e52f956f75f62d3240cf89d69c90b6505a4
diff --git a/include/__libunwind_config.h b/include/__libunwind_config.h
index 343934e..980d11e 100644
--- a/include/__libunwind_config.h
+++ b/include/__libunwind_config.h
@@ -212,11 +212,13 @@
# define _LIBUNWIND_HIGHEST_DWARF_REGISTER 287
#endif // _LIBUNWIND_IS_NATIVE_ONLY
-#if __has_feature(ptrauth_calls) && __has_feature(ptrauth_returns)
-# define _LIBUNWIND_TARGET_AARCH64_AUTHENTICATED_UNWINDING 1
-#elif __has_feature(ptrauth_calls) != __has_feature(ptrauth_returns)
-# error "Either both or none of ptrauth_calls and ptrauth_returns "\
- "is allowed to be enabled"
+#if defined(__has_feature)
+# if __has_feature(ptrauth_calls) && __has_feature(ptrauth_returns)
+# define _LIBUNWIND_TARGET_AARCH64_AUTHENTICATED_UNWINDING 1
+# elif __has_feature(ptrauth_calls) != __has_feature(ptrauth_returns)
+# error "Either both or none of ptrauth_calls and ptrauth_returns "\
+ "is allowed to be enabled"
+# endif
#endif
#endif // ____LIBUNWIND_CONFIG_H__
diff --git a/src/UnwindRegistersRestore.S b/src/UnwindRegistersRestore.S
index 1ab4c43..198735f 100644
--- a/src/UnwindRegistersRestore.S
+++ b/src/UnwindRegistersRestore.S
@@ -634,6 +634,10 @@
#elif defined(__aarch64__)
+#ifndef __has_feature
+#define __has_feature(__feature) 0
+#endif
+
#if defined(__ARM_FEATURE_GCS_DEFAULT)
.arch_extension gcs
#endif
diff --git a/src/UnwindRegistersSave.S b/src/UnwindRegistersSave.S
index 31a177f..619a597 100644
--- a/src/UnwindRegistersSave.S
+++ b/src/UnwindRegistersSave.S
@@ -763,6 +763,10 @@
#elif defined(__aarch64__)
+#ifndef __has_feature
+#define __has_feature(__feature) 0
+#endif
+
//
// extern int __unw_getcontext(unw_context_t* thread_state)
//
