Use ToLower(...) instead of std::tolower

src/uint256.cpp

@@ -33,7 +33,7 @@ void base_blob<BITS>::SetHex(const char* psz)
         psz++;
 
     // skip 0x
-    if (psz[0] == '0' && tolower(psz[1]) == 'x')
+    if (psz[0] == '0' && ToLower((unsigned char)psz[1]) == 'x')
         psz += 2;
 
     // hex string to uint

src/util/system.cpp

@@ -422,7 +422,7 @@ bool ArgsManager::ParseParameters(int argc, const char* const argv[], std::strin
             key.erase(is_index);
         }
 #ifdef WIN32
-        std::transform(key.begin(), key.end(), key.begin(), ::tolower);
+        std::transform(key.begin(), key.end(), key.begin(), ToLower);
         if (key[0] == '/')
             key[0] = '-';
 #endif

test/lint/lint-locale-dependence.sh

@@ -15,10 +15,8 @@ KNOWN_VIOLATIONS=(
     "src/test/getarg_tests.cpp.*split"
     "src/torcontrol.cpp:.*atoi"
     "src/torcontrol.cpp:.*strtol"
-    "src/uint256.cpp:.*tolower"
     "src/util/system.cpp:.*atoi"
     "src/util/system.cpp:.*fprintf"
-    "src/util/system.cpp:.*tolower"
     "src/util/strencodings.cpp:.*atoi"
     "src/util/strencodings.cpp:.*strtol"
     "src/util/strencodings.cpp:.*strtoul"