On Dec 7, 2010, at 6:14 PM, Perry E. Metzger wrote:

On Tue, 7 Dec 2010 16:13:13 -0800 Laurent Sansonetti
<lsansonetti@apple.com> wrote:
Hi Saul,

Did you install the BridgeSupport preview 1 release? Without it, C
blocks won't work in MacRuby.

http://www.macruby.org/blog/2010/10/08/bridgesupport-preview.html

Even without the BridgeSupport stuff, it should not segfault, it
should error out, preferably with a human comprehensible error. It is
bad behavior for an HLL interpreter to register its displeasure by
crashing…

Agreed, however we can't avoid crashing here, as this happens in the C/Objective-C side of the bridge. MacRuby will let you pass most objects to native APIs, but without proper BridgeSupport signatures, these objects might not be properly converted.

In this case, NSArray tries to call something that isn't a pointer to a block function. And the Objective-C runtime doesn't annotate properly block arguments, so BridgeSupport signatures are needed by MacRuby.