"Crop with aspect" Not Working Properly on Transform Tools

Environment/Versions

• GIMP version: 2.10.30
• Package: Windows installer from gimp.org direct install
• Operating System: Windows

Description of the bug

When selecting the "Crop with aspect" option from the "Clipping" dropdown for pretty much all the transform tools, it does not yield an accurate result. For example, it may select a much smaller area of the image as the result of the transformation than what is available. For example, in the image below, I used the Shear transform tool with "Crop with aspect" enabled. The red area was the area that it produced, while the green area is a much larger area that was available using the same aspect ratio as the original image that the program overlooked. It appears this happens on all the transform tools - the Clipping setting isn't properly choosing the largest available area for the given aspect ratio.

This appears to be the cause of bug #7575 as well.

Reproduction

Is the bug reproducible? Always

Reproduction steps:

1. Select a Transform Tool
2. Choose "Crop with aspect" for Clipping option
3. Transform the image/layer.

…

Expected result: Largest available area with same aspect ratio as original image/layer is selected

Actual result: A small, seemingly random or just generally inaccurate area with same aspect ratio as original image is selected.

Additional information

If you have a backtrace for a crash or a warning, paste it here.