The DSTEVR documentation notes that VL/VU are not referenced in A and I modes:
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* VL (input) DOUBLE PRECISION
* VU (input) DOUBLE PRECISION
* If RANGE='V', the lower and upper bounds of the interval to
* be searched for eigenvalues. VL < VU.
* Not referenced if RANGE = 'A' or 'I'.
However, lines 326-327 in dstevr.f contain
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VLL = VL
VUU = VU
I'm not sure on the exact meaning of "not referenced" in the documentation, but in case it is intended to mean that any memory address can be passed in, here's a bug report.

