ICU-12992 new version of the aliasing barrier

X-SVN-Rev: 39739

diff --git a/icu4c/source/common/unicode/char16ptr.h b/icu4c/source/common/unicode/char16ptr.h
index 780a1502738cf9f05e27696a30f387ce9ef89f27..d484cfdf8ac2d0595a9c25b749e0baaccb1d2333 100644 (file)
--- a/icu4c/source/common/unicode/char16ptr.h
+++ b/icu4c/source/common/unicode/char16ptr.h
@@ -25,8 +25,8 @@ U_NAMESPACE_BEGIN
  */
 #ifdef U_ALIASING_BARRIER
     // Use the predefined value.
-#elif 0 // TODO: only some versions of clang?? defined(__clang__) || defined(__GNUC__)
-#   define U_ALIASING_BARRIER(ptr) asm volatile("" : "+rm"(ptr))
+#elif defined(__clang__) || defined(__GNUC__)
+#   define U_ALIASING_BARRIER(ptr) asm volatile("" : : "rm"(ptr) : "memory")
 #endif
 
 /**