1. Bug C, the segfault, also happens with mzscheme v372.
2. Eli Barzilay has been unable to reproduce it in several versions. (http://bugs.plt-scheme.org/query/?cmd=view&pr=10800)
Perhaps it's the fact that I'm running 32-bit EC2 slices. I'm going to fire up a 64-bit instance and try it out.
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