Add misc\get-date.c

Prints the current date as YYYYMMDD without relying on PowerShell.

Hopefully fixes #4540

build.bat

@@ -19,7 +19,11 @@ if "%VSCMD_ARG_TGT_ARCH%" neq "x64" (
 	)
 )
 
-for /f %%i in ('powershell get-date -format "{yyyyMMdd}"') do (
+pushd misc
+cl get-date.c
+popd
+
+for /f %%i in ('misc\get-date') do (
 	set CURR_DATE_TIME=%%i
 )
 set curr_year=%CURR_DATE_TIME:~0,4%
@@ -58,7 +62,6 @@ set V4=0
 set odin_version_full="%V1%.%V2%.%V3%.%V4%"
 set odin_version_raw="dev-%V1%-%V2%"
 
-
 set compiler_flags= -nologo -Oi -TP -fp:precise -Gm- -MP -FC -EHsc- -GR- -GF
 rem Parse source code as utf-8 even on shift-jis and other codepages
 rem See https://learn.microsoft.com/en-us/cpp/build/reference/utf-8-set-source-and-executable-character-sets-to-utf-8?view=msvc-170

misc/get-date.c

@@ -0,0 +1,13 @@
+/*
+	Prints the current date as YYYYMMDD
+
+	e.g. 2024-12-25
+*/
+#include <stdio.h>
+#include <time.h>
+
+int main(int arg_count, char const **arg_ptr) {
+	time_t t = time(NULL);
+	struct tm* now = localtime(&t);
+	printf("%04d%02d%02d", now->tm_year + 1900, now->tm_mon + 1, now->tm_mday);
+}