>>52 here...
>>58
the argv[0] was used because i thought maybe HAHAHaruhi would change it to argv[1], which would be a bug.

but there are other bugs as well:
first...

$ gcc -lm -o hahafail hahafail.c
/var/tmp//ccBv2HKb.o(.text+0x41): In function `main':
: undefined reference to `sqrtl'

second... an intmax_t value is not guaranteed to fit in a long double.