Created attachment 803 [details]
Patch against dmd r737, handles typeCombine errors

In-place array operation "x[] op= y" causes a segfault if the types of x and y
are incompatible for that array op.
----------
void main()
{
    int[] arr;
    arr[] *= 1.5;       // (4)
}
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% dmd -o- -c test.d
test.d(4): Error: incompatible types for ((arr[]) *= (1.5)): 'int[]' and
'double'
zsh: segmentation fault (core dumped)  dmd -o- -c test.d
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The segfault happens in BinExp::arrayOp() when its type is TypeError because of
the incompatible types.  The proposed patch makes it sure that the error
condition is handled before arrayOp().