[core] fix a crash due to overzealous MSVC optimizations

* Visual 2022 version 17.14.2 changes the way it performs optimizations with /O2
  which results in innocuous C statements, such as invoking strtoul() twice on
  the same line, and using the pointer returned by the first call in the second,
  crashing the application with a read access violation (when built as RELEASE).
* To alleviate that, we break down the Syslinux strtoul() invocation, as well as
  harden our Syslinux version processing while we're at it.
* Hopefully this is the only line of code where the new mode of MSVC optimisation
  creates a problem with...
* Closes #2740.

src/rufus.rc

@@ -33,7 +33,7 @@ LANGUAGE LANG_NEUTRAL, SUBLANG_NEUTRAL
 IDD_DIALOG DIALOGEX 12, 12, 232, 326
 STYLE DS_SETFONT | DS_MODALFRAME | DS_CENTER | WS_MINIMIZEBOX | WS_POPUP | WS_CAPTION | WS_SYSMENU
 EXSTYLE WS_EX_ACCEPTFILES
-CAPTION "Rufus 4.8.2248"
+CAPTION "Rufus 4.8.2249"
 FONT 9, "Segoe UI Symbol", 400, 0, 0x0
 BEGIN
     LTEXT           "Drive Properties",IDS_DRIVE_PROPERTIES_TXT,8,6,53,12,NOT WS_GROUP
@@ -407,8 +407,8 @@ END
 //
 
 VS_VERSION_INFO VERSIONINFO
- FILEVERSION 4,8,2248,0
- PRODUCTVERSION 4,8,2248,0
+ FILEVERSION 4,8,2249,0
+ PRODUCTVERSION 4,8,2249,0
  FILEFLAGSMASK 0x3fL
 #ifdef _DEBUG
  FILEFLAGS 0x1L
@@ -426,13 +426,13 @@ BEGIN
             VALUE "Comments", "https://rufus.ie"
             VALUE "CompanyName", "Akeo Consulting"
             VALUE "FileDescription", "Rufus"
-            VALUE "FileVersion", "4.8.2248"
+            VALUE "FileVersion", "4.8.2249"
             VALUE "InternalName", "Rufus"
             VALUE "LegalCopyright", "© 2011-2025 Pete Batard (GPL v3)"
             VALUE "LegalTrademarks", "https://www.gnu.org/licenses/gpl-3.0.html"
             VALUE "OriginalFilename", "rufus-4.8.exe"
             VALUE "ProductName", "Rufus"
-            VALUE "ProductVersion", "4.8.2248"
+            VALUE "ProductVersion", "4.8.2249"
         END
     END
     BLOCK "VarFileInfo"

src/syslinux.c

@@ -400,8 +400,9 @@ out:
 uint16_t GetSyslinuxVersion(char* buf, size_t buf_size, char** ext)
 {
 	size_t i, j, k;
-	char *p;
-	uint16_t version;
+	char *p = NULL;
+	unsigned long version_ul[2];
+	uint16_t version = 0;
 	const char LINUX[] = { 'L', 'I', 'N', 'U', 'X', ' ' };
 	static char* nullstr = "";
 	char unauthorized[] = {'<', '>', ':', '|', '*', '?', '\\', '/'};
@@ -418,10 +419,17 @@ uint16_t GetSyslinuxVersion(char* buf, size_t buf_size, char** ext)
 			    || ((buf[i - 3] == 'S') && (buf[i - 2] == 'Y') && (buf[i - 1] == 'S')) ))
 			  continue;
 			i += sizeof(LINUX);
-			version = (((uint8_t)strtoul(&buf[i], &p, 10)) << 8) + (uint8_t)strtoul(&p[1], &p, 10);
+			version_ul[0] = strtoul(&buf[i], &p, 10);
 			// Our buffer is either from our internal legit syslinux (i.e. with a NUL terminated
 			// version string) or from a buffer that has been NUL-terminated through read_file(),
 			// so the string we work with in p is always NUL terminated at this stage.
+			assert(version_ul[0] < 256);
+			if (version_ul[0] < 256) {
+				version_ul[1] = strtoul(&p[1], &p, 10);
+				assert(version_ul[1] < 256);
+				if (version_ul[1] < 256)
+					version = (uint16_t)((version_ul[0] << 8) + version_ul[1]);
+			}
 			if (version == 0)
 				continue;
 			// Ensure that our extra version string starts with a slash