Compiler crashes when using the a,b=b,a syntax on large arrays

[hstormo]

Context

        Odin:    dev-2024-05:d698d4cda
        OS:      Windows 11 Enterprise (version: 23H2), build 22631.3296
        CPU:     AMD Ryzen 7 5800X 8-Core Processor
        RAM:     16310 MiB
        Backend: LLVM 17.0.1

package main

a, b: [100000]int

main :: proc() {
    a, b = b, a
}

Expected Behavior

The program should compile, probably with a "possible stack overflow" warning like it does if you declare a large array as local variable.

Current Behavior

The compiler crashes.

Steps to Reproduce

Compile the code above.

[hstormo]

Tried in the debugger, shows segfault in llvm call.

[gingerBill]

This isn't a bug per se, but rather just a possible stack overflow. So it's a question how would you warn about such a thing in the first place?

[hstormo]

Well, if I swap the arrays the "traditional" way with a temporary variable, like t := a; a = b; b = t it compiles fine with a warning: Warning: Declaration of 't' may cause a stack overflow due to its type '[100000]int' having a size of 800000 bytes So I assumed the same would be possible with the special syntax. But I don't know how it's actually implemented.