Fix "unsafe narrowing" warnings in absl, 4/n.

Addresses failures with the following, in some files:
-Wshorten-64-to-32
-Wimplicit-int-conversion
-Wsign-compare
-Wsign-conversion
-Wtautological-unsigned-zero-compare

(This specific CL focuses on .cc files in strings/, except /internal/.)

Bug: chromium:1292951
PiperOrigin-RevId: 468205572
Change-Id: Ifce3f1a7a4b2b2c359bf7700a11279bebfef8a15

1 files changed, 5 insertions, 5 deletions

diff --git a/absl/strings/ascii.cc b/absl/strings/ascii.cc
index 93bb03e9..868df2d1 100644
--- a/absl/strings/ascii.cc
+++ b/absl/strings/ascii.cc
@@ -157,13 +157,13 @@ ABSL_DLL const char kToUpper[256] = {
 
 void AsciiStrToLower(std::string* s) {
   for (auto& ch : *s) {
-    ch = absl::ascii_tolower(ch);
+    ch = absl::ascii_tolower(static_cast<unsigned char>(ch));
   }
 }
 
 void AsciiStrToUpper(std::string* s) {
   for (auto& ch : *s) {
-    ch = absl::ascii_toupper(ch);
+    ch = absl::ascii_toupper(static_cast<unsigned char>(ch));
   }
 }
 
@@ -183,17 +183,17 @@ void RemoveExtraAsciiWhitespace(std::string* str) {
   for (; input_it < input_end; ++input_it) {
     if (is_ws) {
       // Consecutive whitespace?  Keep only the last.
-      is_ws = absl::ascii_isspace(*input_it);
+      is_ws = absl::ascii_isspace(static_cast<unsigned char>(*input_it));
       if (is_ws) --output_it;
     } else {
-      is_ws = absl::ascii_isspace(*input_it);
+      is_ws = absl::ascii_isspace(static_cast<unsigned char>(*input_it));
     }
 
     *output_it = *input_it;
     ++output_it;
   }
 
-  str->erase(output_it - &(*str)[0]);
+  str->erase(static_cast<size_t>(output_it - &(*str)[0]));
 }
 
 ABSL_NAMESPACE_END