PR #1559: Fix comparison of integer expressions of different signedness warning

aligusnet · copybara-github · commit 7135ec61db16 · 2023-11-02T10:21:14.000-07:00
Imported from GitHub PR #1559 ``` //absl/hash/internal/hash.h:633:21: error: comparison of integer expressions of different signedness: 'int' and 'long unsigned int' [-Werror=sign-compare] ``` This warning is specific to the hashing of `std::bitset<>` on Big Endian platforms such as s390x Merge 3f34d80 into 065d50d Merging this change closes #1559 COPYBARA_INTEGRATE_REVIEW=#1559 from aligusnet:20211102.0-mongo 3f34d80 PiperOrigin-RevId: 578897545 Change-Id: Ifd1c947af3ad01e8e2a6241030ed29fb00842d53
diff --git a/absl/hash/internal/hash.h b/absl/hash/internal/hash.h
@@ -818,7 +818,7 @@ AbslHashValue(H hash_state, const absl::variant<T...>& v) {
 template <typename H, size_t N>
 H AbslHashValue(H hash_state, const std::bitset<N>& set) {
   typename H::AbslInternalPiecewiseCombiner combiner;
-  for (int i = 0; i < N; i++) {
+  for (size_t i = 0; i < N; i++) {
     unsigned char c = static_cast<unsigned char>(set[i]);
     hash_state = combiner.add_buffer(std::move(hash_state), &c, sizeof(c));
   }

Original file line number	Diff line number	Diff line change
`@@ -818,7 +818,7 @@ AbslHashValue(H hash_state, const absl::variant<T...>& v) {`
`818`	`818`	`template <typename H, size_t N>`
`819`	`819`	`H AbslHashValue(H hash_state, const std::bitset<N>& set) {`
`820`	`820`	`typename H::AbslInternalPiecewiseCombiner combiner;`
`821`		`- for (int i = 0; i < N; i++) {`
	`821`	`+ for (size_t i = 0; i < N; i++) {`
`822`	`822`	`unsigned char c = static_cast<unsigned char>(set[i]);`
`823`	`823`	`hash_state = combiner.add_buffer(std::move(hash_state), &c, sizeof(c));`
`824`	`824`	`}`