Fix the way malloc debug returns info.
When I rewrote malloc debug, I accidentally thought that each
value returned in the info buffer contained the number of backtrace
frames in the backtrace. This was incorrect, it should have been
the total number of allocations with the same backtrace.
This is a temporary fix that sets that value to 1. The better fix is
to de-dupe backtraces and then return all allocations of the same size
with the same backtrace.
I updated the documents to describe this.
Bug: 31854476
Test: Unit tests pass.
Change-Id: Idf9efaa3d363923b5d7543d90dc7c65a0ed553d9
diff --git a/libc/malloc_debug/TrackData.cpp b/libc/malloc_debug/TrackData.cpp
index 18f428b..d4064f8 100644
--- a/libc/malloc_debug/TrackData.cpp
+++ b/libc/malloc_debug/TrackData.cpp
@@ -123,11 +123,12 @@
GetList(&list);
uint8_t* data = *info;
+ size_t num_allocations = 1;
for (const auto& header : list) {
BacktraceHeader* back_header = debug_->GetAllocBacktrace(header);
if (back_header->num_frames > 0) {
memcpy(data, &header->size, sizeof(size_t));
- memcpy(&data[sizeof(size_t)], &back_header->num_frames, sizeof(size_t));
+ memcpy(&data[sizeof(size_t)], &num_allocations, sizeof(size_t));
memcpy(&data[2 * sizeof(size_t)], &back_header->frames[0],
back_header->num_frames * sizeof(uintptr_t));