Assigned interior causes a bad allocation error

[CousinRicky]

Summary

Declaring an interior, and then assigning it to another variable causes POV-Ray to halt with a bad allocation error.

POV-Ray Version

• Incarnation: POV-Ray for Unix
• Affected build version: 3.8.0-beta.2.unofficial (self-compiled)
• Known working build version: 3.7.0.10

Runtime Environment

• Operating system: openSUSE 15.3 GNU/Linux
• Hardware: Lenovo Ideapad Slim 7
• Hardware architecture: x86-64
• CPU model: Intel Core i7

Scene

#version max (3.5, min (3.8, version));
global_settings { assumed_gamma 1 }
#declare Int = interior { ior 1.5 }
#declare myInt = Int

Expected Behavior

Scene renders to completion. (This minimal scene has no objects.)

Actual Behavior

The render halts during the parsing phase.

Output

==== [Parsing...] ==========================================================
File 'tmp.pov' line 4: Parse Error: std::bad_alloc
Fatal error in parser: Cannot parse input.
Render failed

Additional context

This bug was first reported in povray.beta-test: Assigning an interior crashes 3.8 beta 2.

Workaround

Wrapping the right-hand identifier with an interior block avoids the crash. In the example, replace line 4 with #declare myInt = interior { Int }

Suggested Solution

See wfpokorny’s analysis in the p.beta-test thread.