v.pref: fix `-nocache`, add `-no-retry-compilation`, add `-d trace_use_cache`

vlib/v/builder/cc.v

@@ -611,6 +611,9 @@ fn (mut v Builder) cc() {
 			v.show_c_compiler_output(res)
 		}
 		os.chdir(original_pwd)
+		$if trace_use_cache ? {
+			eprintln('>>>> v.pref.use_cache: $v.pref.use_cache | v.pref.retry_compilation: $v.pref.retry_compilation | cmd res.exit_code: $res.exit_code | cmd: $cmd')
+		}
 		if res.exit_code != 0 {
 			if ccompiler.contains('tcc.exe') {
 				// a TCC problem? Retry with the system cc:
@@ -621,9 +624,11 @@ fn (mut v Builder) cc() {
 					}
 					exit(101)
 				}
-				v.pref.ccompiler = pref.default_c_compiler()
-				eprintln('Compilation with tcc failed. Retrying with $v.pref.ccompiler ...')
-				continue
+				if v.pref.retry_compilation {
+					v.pref.ccompiler = pref.default_c_compiler()
+					eprintln('Compilation with tcc failed. Retrying with $v.pref.ccompiler ...')
+					continue
+				}
 			}
 			if res.exit_code == 127 {
 				verror('C compiler error, while attempting to run: \n' +

vlib/v/pref/default.v

@@ -94,9 +94,18 @@ pub fn (mut p Preferences) fill_with_defaults() {
 		'$p.lookup_path',
 	])
 	// eprintln('prefs.cache_manager: $p')
-	//
-	// enable use_cache by default
-	// p.use_cache = os.user_os() != 'windows'
+	// disable use_cache for specific cases:
+	if os.user_os() == 'windows' {
+		p.use_cache = false
+	}
+	if p.build_mode == .build_module {
+		// eprintln('-usecache and build-module flags are not compatible')
+		p.use_cache = false
+	}
+	if p.is_shared {
+		// eprintln('-usecache and -shared flags are not compatible')
+		p.use_cache = false
+	}
 }
 
 fn (mut p Preferences) find_cc_if_cross_compiling() {

vlib/v/pref/pref.v

@@ -79,7 +79,7 @@ pub mut:
 	// which are sometimes easier to debug / inspect manually than the .tmp.c files by plain -g (when/if v line number generation breaks).
 	// use cached modules to speed up compilation.
 	use_cache           bool // = true
-	no_cache            bool
+	retry_compilation   bool = true
 	is_stats            bool // `v -stats file_test.v` will produce more detailed statistics for the tests that were run
 	no_auto_free        bool // `v -nofree` disable automatic `free()` insertion for better performance in some applications  (e.g. compilers)
 	// TODO Convert this into a []string
@@ -220,6 +220,9 @@ pub fn parse_args(args []string) (&Preferences, string) {
 				res.is_bare = true
 				res.build_options << arg
 			}
+			'-no-retry-compilation' {
+				res.retry_compilation = false
+			}
 			'-no-preludes' {
 				res.no_preludes = true
 				res.build_options << arg
@@ -276,7 +279,7 @@ pub fn parse_args(args []string) (&Preferences, string) {
 				res.use_cache = true
 			}
 			'-nocache' {
-				res.no_cache = true
+				res.use_cache = false
 			}
 			'-prealloc' {
 				res.prealloc = true