commit f9ed158e41d8efb47182aa38658ca4f8c81131b3
author Leonard Chan <leonardchan@google.com> Tue May 24 11:29:44 2022 -0700
committer Copybara-Service <copybara-worker@google.com> Tue May 24 11:36:27 2022 -0700
tree db19eebac1fa0137c58370958cf5edaa456072a4
parent 7c6da15826e1900a68abd84f1501938e57769830

Revert "[compiler-rt][scudo] Add missing preprocessor token" and "[compiler-rt][scudo] Simplify TBI checks"

This reverts commit 676eaa2ca967ca6ad4a84d31d6f0ebabdcf3e44b
and f6038cdca03115da22b9e6ada5c25de4df5f42d2 since builders are still
broken.

GitOrigin-RevId: 6edbdf80cac119f8f30d2ae6fa2972d9e778510b

memtag.h

diff --git a/memtag.h b/memtag.h
index d65e76a..7f14a30 100644
--- a/memtag.h
+++ b/memtag.h
@@ -18,16 +18,19 @@
 
 namespace scudo {
 
+#if (__clang_major__ >= 12 && defined(__aarch64__) && !defined(__ILP32__)) ||  \
+    defined(SCUDO_FUZZ)
+
 // We assume that Top-Byte Ignore is enabled if the architecture supports memory
 // tagging. Not all operating systems enable TBI, so we only claim architectural
 // support for memory tagging if the operating system enables TBI.
 // HWASan uses the top byte for its own purpose and Scudo should not touch it.
-#if (__clang_major__ >= 12 && defined(__aarch64__) && !defined(__ILP32__) &&   \
-     SCUDO_LINUX && !defined(SCUDO_DISABLE_TBI) &&                             \
-     !__has_feature(hwaddress_sanitizer)) ||                                   \
-    defined(SCUDO_FUZZ)
-
+#if SCUDO_LINUX && !defined(SCUDO_DISABLE_TBI) &&                              \
+    !__has_feature(hwaddress_sanitizer)
 inline constexpr bool archSupportsMemoryTagging() { return true; }
+#else
+inline constexpr bool archSupportsMemoryTagging() { return false; }
+#endif
 
 inline constexpr uptr archMemoryTagGranuleSize() { return 16; }