Seen with llvm 17 on Windows x64.
```
.../curl/tests/server/rtspd.c:136:13: warning: no previous extern declaration for non-static variable 'logdir' [-Wmissing-variable-declarations]
136 | const char *logdir = "log";
| ^
.../curl/tests/server/rtspd.c:136:7: note: declare 'static' if the variable is not intended to be used outside of this translation unit
136 | const char *logdir = "log";
| ^
.../curl/tests/server/rtspd.c:137:6: warning: no previous extern declaration for non-static variable 'loglockfile' [-Wmissing-variable-declarations]
137 | char loglockfile[256];
| ^
.../curl/tests/server/rtspd.c:137:1: note: declare 'static' if the variable is not intended to be used outside of this translation unit
137 | char loglockfile[256];
| ^
.../curl/tests/server/fake_ntlm.c:43:13: warning: no previous extern declaration for non-static variable 'logdir' [-Wmissing-variable-declarations]
43 | const char *logdir = "log";
| ^
.../curl/tests/server/fake_ntlm.c:43:7: note: declare 'static' if the variable is not intended to be used outside of this translation unit
43 | const char *logdir = "log";
| ^
.../curl/src/tool_doswin.c:350:8: warning: possible misuse of comma operator here [-Wcomma]
350 | ++d, ++s;
| ^
.../curl/src/tool_doswin.c:350:5: note: cast expression to void to silence warning
350 | ++d, ++s;
| ^~~
| (void)( )
```
```
.../curl/tests/libtest/lib540.c:146:27: warning: result of comparison 'long' > 2147483647 is always false [-Wtautological-type-limit-compare]
146 | int itimeout = (L > (long)INT_MAX) ? INT_MAX : (int)L;
| ~ ^ ~~~~~~~~~~~~~
1 warning generated.
.../curl/tests/libtest/libntlmconnect.c:195:31: warning: result of comparison 'long' > 2147483647 is always false [-Wtautological-type-limit-compare]
195 | int itimeout = (timeout > (long)INT_MAX) ? INT_MAX : (int)timeout;
| ~~~~~~~ ^ ~~~~~~~~~~~~~
1 warning generated.
.../curl/tests/libtest/lib591.c:117:31: warning: result of comparison 'long' > 2147483647 is always false [-Wtautological-type-limit-compare]
117 | int itimeout = (timeout > (long)INT_MAX) ? INT_MAX : (int)timeout;
| ~~~~~~~ ^ ~~~~~~~~~~~~~
1 warning generated.
.../curl/tests/libtest/lib597.c:99:31: warning: result of comparison 'long' > 2147483647 is always false [-Wtautological-type-limit-compare]
99 | int itimeout = (timeout > (long)INT_MAX) ? INT_MAX : (int)timeout;
| ~~~~~~~ ^ ~~~~~~~~~~~~~
1 warning generated.
```
Seen on macOS Intel:
```
.../curl/tests/server/sws.c:440:64: warning: field precision should have type 'int', but argument has type 'size_t' (aka 'unsigned long') [-Wformat]
msnprintf(logbuf, sizeof(logbuf), "Got request: %s %.*s HTTP/%d.%d",
~~^~
1 warning generated.
```
Closes#11925