Blocks whose largest nonzero value is subnormal can cause floating-point overflow during conversion to zfp's block-floating-point format. Although this conversion corrupts the mantissas, this is an otherwise benign bug as such blocks are still reconstructed as a collection of "random" subnormals, albeit with complete loss of precision.

Two potential solutions have been identified:

• Perform the float-to-int normalization in two steps via two separate multipliers. This will, however, incur a performance penalty for all blocks.
• Cap the smallest supported block exponent, which effectively flushes subnormals to zero (a strategy already employed by many processors). Given that the tolerances used with zfp often vastly exceed FLT_MIN, this should have a negligible effect in practice. Whereas this approach affects the compressed representation of all-subnormal blocks, current versions of zfp would still correctly decompress such blocks.