September 18, 2022
https://issues.dlang.org/show_bug.cgi?id=23342

          Issue ID: 23342
           Summary: ImportC: Array compound literals use the GC
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: ImportC
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: dave287091@gmail.com

6.5.2.4.5 states:

> The value of the compound literal is that of an unnamed object initialized by the initializer list. If the compound literal occurs outside the body of a function, the object has static storage duration; otherwise, it has automatic storage duration associated with the enclosing block.

ImportC apparently creates them with the GC, as evidenced with the following C program:

// arr.c
int main(){
    int* p = (int[]){3}; // Error: expression `[3]` uses the GC and cannot be
used with switch `-betterC`
    return 0;
}

Compiling it with -betterC reveals the problem.

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