1 files changed, 4 insertions, 4 deletions
diff --git a/absl/numeric/int128.h b/absl/numeric/int128.h
index bd1b553..94d2f7c 100644
--- a/absl/numeric/int128.h
+++ b/absl/numeric/int128.h
@@ -511,8 +511,8 @@ inline uint128& uint128::operator^=(uint128 other) {
 // Shift and arithmetic assign operators.
 
 inline uint128& uint128::operator<<=(int amount) {
-  // Shifts of >= 128 are undefined.
-  assert(amount < 128);
+  assert(amount >= 0);   // Negative shifts are undefined.
+  assert(amount < 128);  // Shifts of >= 128 are undefined.
 
   // uint64_t shifts of >= 64 are undefined, so we will need some
   // special-casing.
@@ -529,8 +529,8 @@ inline uint128& uint128::operator<<=(int amount) {
 }
 
 inline uint128& uint128::operator>>=(int amount) {
-  // Shifts of >= 128 are undefined.
-  assert(amount < 128);
+  assert(amount >= 0);   // Negative shifts are undefined.
+  assert(amount < 128);  // Shifts of >= 128 are undefined.
 
   // uint64_t shifts of >= 64 are undefined, so we will need some
   // special-casing.