ICU-20048 Remove use of std::align() for compat with g++ 4.9.
diff --git a/icu4c/source/common/ucnv.cpp b/icu4c/source/common/ucnv.cpp
index 8f94a28..856be70 100644
--- a/icu4c/source/common/ucnv.cpp
+++ b/icu4c/source/common/ucnv.cpp
@@ -225,13 +225,16 @@
}
}
-
/* Adjust (if necessary) the stackBuffer pointer to be aligned correctly for a UConverter.
+ * TODO(Jira ICU-20736) Redo this using std::align() once g++4.9 compatibility is no longer needed.
*/
- size_t altStackBufferSize = stackBufferSize; // Incompatible types for passing by reference.
if (stackBuffer) {
- if (std::align(alignof(UConverter), bufferSizeNeeded, stackBuffer, altStackBufferSize)) {
- stackBufferSize = static_cast<int32_t>(altStackBufferSize);
+ uintptr_t p = reinterpret_cast<uintptr_t>(stackBuffer);
+ uintptr_t aligned_p = (p + alignof(UConverter) - 1) & ~(alignof(UConverter) - 1);
+ ptrdiff_t pointerAdjustment = aligned_p - p;
+ if (bufferSizeNeeded + pointerAdjustment <= stackBufferSize) {
+ stackBuffer = reinterpret_cast<void *>(aligned_p);
+ stackBufferSize -= pointerAdjustment;
} else {
/* prevent using the stack buffer but keep the size > 0 so that we do not just preflight */
stackBufferSize = 1;
