Error: pointer being freed was not allocated when specifying bogus amount of context

[Andreas Lind]

I "accidentally" tried setting a negative amount of before context and got:

$ ag foo . -B-1
ag(31443,0x70000c51c000) malloc: *** error for object 0xf000000000000000: pointer being freed was not allocated
ag(31443,0x70000c393000) malloc: *** error for object 0x7274732065737527: pointer being freed was not allocated
ag(31443,0x70000c51c000) malloc: *** set a breakpoint in malloc_error_break to debug
ag(31443,0x70000c393000) malloc: *** set a breakpoint in malloc_error_break to debug
Abort trap: 6

I'm using ag version 2.2.0 on OSX 11.6.1 (20G224), installed using homebrew.