Fix Issue 23705 - dmd: src/dmd/backend/cgcod.d:734: Assertion sz >= 0 failed

[RazvanN7]

Targeting master as this manifests in non-release builds, although it might have negative effects on release builds also.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	23705	critical	dmd: src/dmd/backend/cgcod.d:734: Assertion `sz >= 0' failed.

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "stable + dmd#14876"

[RazvanN7]

targ_size_t is an alias to ulong, therefore casting to int gets a part of the number.

[ibuclaw]

Isn't release logically deprecated? ICE is an ICE is an ICE. You should never be able to crash the compiler whatever you're doing.

[RazvanN7]

Fair enough. Targeting stable now.

[ibuclaw]

This test fails on many platforms - especially i686 and other 32-bit architectures - as there is no space for the frame pointer - does this fail with a smaller number?

[dkorpel]

I don't think so, but perhaps static if (size_t.sizeof > 4) could be added.

[ibuclaw]

FAOD, GCC enforces that the maximum size for local variables to occupy the stack to be:

ubyte [(1 << (size_t.sizeof * 8 - 1)) - 64 * size_t.sizeof] x;

That is per function, not per variable.