ci: fix windows-msvc builds, as well as the windows-cross job, turn on deprecation notices for [windows_stdcall] and [_fastcall]

.github/workflows/ci_cross.yml

@@ -77,7 +77,7 @@ jobs:
 
       - name: v_win.c can be compiled and run with -os windows
         run: |
-          ./v -os windows -o /tmp/v_win.c cmd/v
+          ./v -cc msvc -os windows -o /tmp/v_win.c cmd/v
           x86_64-w64-mingw32-gcc -I ./thirdparty/stdatomic/win /tmp/v_win.c -std=c99 -w -municode -o v_from_vc.exe
           ls -lart v_from_vc.exe
           wine64 ./v_from_vc.exe version
@@ -102,8 +102,6 @@ jobs:
   windows-cross:
     runs-on: windows-2019
     timeout-minutes: 25
-    env:
-      VFLAGS: -cc msvc
     steps:
       - uses: actions/checkout@v2
       - name: Build
@@ -113,8 +111,8 @@ jobs:
           .\make.bat -msvc
       - name: TODO v_win.c can be compiled and run with -os windows
         run: |
-          .\v.exe -os windows -showcc -o v2.exe cmd\v
-          .\v.exe -os windows -o v_win.c cmd\v
+          .\v.exe -os windows -cc msvc -showcc -o v2.exe cmd\v
+          .\v.exe -os windows -cc msvc -o v_win.c cmd\v
           dir v2.exe
           dir v_win.c
           .\v2.exe version

vlib/builtin/builtin_windows.c.v

@@ -238,7 +238,7 @@ fn add_vectored_exception_handler(handler VectoredExceptionHandler) {
 	C.AddVectoredExceptionHandler(1, C.PVECTORED_EXCEPTION_HANDLER(handler))
 }
 
-[windows_stdcall]
+[callconv: stdcall]
 fn unhandled_exception_handler(e &ExceptionPointers) int {
 	match e.exception_record.code {
 		// These are 'used' by the backtrace printer

vlib/v/parser/fn.v

@@ -222,12 +222,12 @@ fn (mut p Parser) fn_decl() ast.FnDecl {
 				is_markused = true
 			}
 			'windows_stdcall' {
-				// TODO: uncomment after bootstrapping and replacing usages in builtin
-				// p.note_with_pos('windows_stdcall has been deprecated, it will be an error soon', p.tok.pos())
+				p.note_with_pos('the tag [windows_stdcall] has been deprecated, it will be an error after 2022-06-01, use `[callconv: stdcall]` instead',
+					p.tok.pos())
 			}
 			'_fastcall' {
-				// TODO: uncomment after bootstrapping and replacing usages in builtin
-				// p.note_with_pos('_fastcall has been deprecated, it will be an error soon', p.tok.pos())
+				p.note_with_pos('teh tag [_fastcall] has been deprecated, it will be an error after 2022-06-01, use `[callconv: fastcall]` instead',
+					p.tok.pos())
 			}
 			'callconv' {
 				if !fna.has_arg {

vlib/v/tests/create_dll/create_win_dll.v

@@ -14,7 +14,7 @@ pub fn test_tatltuae() int {
 }
 
 [export: DllMain]
-[windows_stdcall]
+[callconv: stdcall]
 fn main(hinst voidptr, fdw_reason int, lp_reserved voidptr) bool {
 	match fdw_reason {
 		C.DLL_PROCESS_ATTACH {