diff --git a/lib/sanitizer_common/sanitizer_stack_store.cpp b/lib/sanitizer_common/sanitizer_stack_store.cpp
index e6c61d9..d46047b 100644
--- a/lib/sanitizer_common/sanitizer_stack_store.cpp
+++ b/lib/sanitizer_common/sanitizer_stack_store.cpp
@@ -16,13 +16,13 @@
 
 namespace {
 struct StackTraceHeader {
-  static constexpr u32 kStackSizeBits = 16;
+  static constexpr u32 kStackSizeBits = 8;
 
-  u32 size;
-  u32 tag;
+  u8 size;
+  u8 tag;
   explicit StackTraceHeader(const StackTrace &trace)
-      : size(trace.size), tag(trace.tag) {
-    CHECK_LT(trace.size, 1 << kStackSizeBits);
+      : size(Min<uptr>(trace.size, (1u << 8) - 1)), tag(trace.tag) {
+    CHECK_EQ(trace.tag, static_cast<uptr>(tag));
   }
   explicit StackTraceHeader(uptr h)
       : size(h & ((1 << kStackSizeBits) - 1)), tag(h >> kStackSizeBits) {}
diff --git a/lib/sanitizer_common/sanitizer_stacktrace.h b/lib/sanitizer_common/sanitizer_stacktrace.h
index 11c6154..aebd504 100644
--- a/lib/sanitizer_common/sanitizer_stacktrace.h
+++ b/lib/sanitizer_common/sanitizer_stacktrace.h
@@ -20,7 +20,7 @@
 
 struct BufferedStackTrace;
 
-static const u32 kStackTraceMax = 256;
+static const u32 kStackTraceMax = 255;
 
 #if SANITIZER_LINUX && defined(__mips__)
 # define SANITIZER_CAN_FAST_UNWIND 0