ccan: don't attempt unaligned access on arm

ElementsProject · May 20, 2023 · 745bc55 · 745bc55
1 parent ec67b98
commit 745bc55
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/src/ccan_config.h b/src/ccan_config.h
@@ -28,6 +28,16 @@
 #define HAVE_BSWAP_64 0
 #endif
 
+#if defined(HAVE_UNALIGNED_ACCESS) && defined(__arm__)
+/* arm unaligned access is incomplete, in that e.g. byte swap instructions
+ * can fault on unaligned addresses where a normal load/store would be fine.
+ * Since the compiler can optimise some of our accesses into operations like
+ * byte swaps, treat this platform as though it doesn't have unaligned access.
+ */
+#undef HAVE_UNALIGNED_ACCESS
+#define HAVE_UNALIGNED_ACCESS 0
+#endif
+
 #if HAVE_UNALIGNED_ACCESS
 #define alignment_ok(p, n) 1
 #else