fix ANSI pathname under windows

vlib/v/builder/builder_test.v

@@ -1,12 +1,14 @@
 module main
 
 import os
+import encoding.iconv
 
 const vexe = @VEXE
 const test_path = os.join_path(os.vtmp_dir(), 'run_check')
+const test_path2 = os.join_path(test_path, '测试目录')
 
 fn testsuite_begin() {
-	os.mkdir_all(test_path) or {}
+	os.mkdir_all(test_path2) or {}
 }
 
 fn testsuite_end() {
@@ -43,3 +45,33 @@ fn test_conditional_executable_removal() {
 	dump(after_second_run___)
 	assert executable in after_second_run___
 }
+
+fn test_windows_ansi_path_name() {
+	os.chdir(test_path2)!
+	os.write_file('测试.v', 'fn main(){\n\tprintln("Hello World!")\n}\n')!
+
+	mut executable := '测试'
+	$if windows {
+		executable += '.exe'
+	}
+
+	original_file_list_ := os.ls(test_path2)!
+	dump(original_file_list_)
+	assert executable !in original_file_list_
+
+	assert os.execute('${os.quoted_path(vexe)} run .').output.trim_space() == 'Hello World!'
+	after_run_file_list := os.ls(test_path2)!.filter(os.exists(it))
+	dump(after_run_file_list)
+	assert executable !in after_run_file_list
+
+	assert os.execute('${os.quoted_path(vexe)} . -o ${executable}').exit_code == 0
+	assert os.execute('./${executable}').output.trim_space() == 'Hello World!'
+	after_compilation__ := os.ls(test_path2)!
+	dump(after_compilation__)
+	assert executable in after_compilation__
+
+	assert os.execute('${os.quoted_path(vexe)} run .').output.trim_space() == 'Hello World!'
+	after_second_run___ := os.ls(test_path2)!
+	dump(after_second_run___)
+	assert executable in after_second_run___
+}

vlib/v/builder/cc.v

@@ -9,6 +9,7 @@ import v.pref
 import v.util
 import v.vcache
 import term
+import encoding.iconv
 
 const c_std = 'c99'
 const c_std_gnu = 'gnu99'
@@ -666,8 +667,15 @@ pub fn (mut v Builder) cc() {
 			response_file_content = str_args.replace('\\', '\\\\')
 			rspexpr := '@${response_file}'
 			cmd = '${v.quote_compiler_name(ccompiler)} ${os.quoted_path(rspexpr)}'
-			os.write_file(response_file, response_file_content) or {
-				verror('Unable to write to C response file "${response_file}"')
+			$if windows {
+				// Windows use ANSI encoding for path/filename
+				// NOTE: use 'ANSI' encoding, not 'UTF-8'
+				iconv.write_file_encoding(response_file, response_file_content, 'ANSI',
+					false) or { verror('Unable to write to C response file "${response_file}"') }
+			} $else {
+				os.write_file(response_file, response_file_content) or {
+					verror('Unable to write to C response file "${response_file}"')
+				}
 			}
 		}
 		if !v.ccoptions.debug_mode {

vlib/v/builder/msvc_windows.v

@@ -4,6 +4,7 @@ import os
 import time
 import v.util
 import v.cflag
+import encoding.iconv
 
 #flag windows -l shell32
 #flag windows -l dbghelp
@@ -357,7 +358,8 @@ pub fn (mut v Builder) cc_msvc() {
 	v.dump_c_options(a)
 	args := a.join(' ')
 	// write args to a file so that we dont smash createprocess
-	os.write_file(out_name_cmd_line, args) or {
+	// NOTE: use 'ANSI' encoding, not 'UTF-8'
+	iconv.write_file_encoding(out_name_cmd_line, args, 'ANSI', false) or {
 		verror('Unable to write response file to "${out_name_cmd_line}"')
 	}
 	cmd := '"${r.full_cl_exe_path}" "@${out_name_cmd_line}"'