IJG jpegtran Windows exe makes jpegultrascan die

[T-3B]

I know some people on Discord who are using jpegultrascan on Windows, and it simply dies when using jpegtran from IJG.

Steps to reproduce (I was able to reproduce the issue on Linux with wine):

• download jpegtran.exe from https://jpegclub.org/jpegtran/ (version is 9f 14-Jan-2024)
• jpegultrascan.pl -t 16 -p ./jpegtran.exe in.jpg out.jpg

Output log is.... 421MB:

Use of uninitialized value $bsize in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $asize in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $bsize in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $asize in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $bscans in concatenation (.) or string at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $bsize in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $asize in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $bsize in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $asize in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.
Use of uninitialized value $ascans in concatenation (.) or string at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 309.

which repeats for a few hundreds of thousand lines, then:

Use of uninitialized value $scans in concatenation (.) or string at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 327.
Use of uninitialized value $size in addition (+) at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 326.

which repeats for a few thousand lines, then:

Calculating sizes and searching for best DC scan
Died at /home/clement_smagghe/programmes/rhefo/jpegultrascan.pl line 110.

Linux seems unaffected by this if compiled from source (download jpegsrc.v9f.tar.gz from https://www.ijg.org, then simply ./configure && make -j).
I don't know if jpegultrascan would still die on Windows if compiled from source (note that the archive to download is not the same as the one for Linux).