[ntp:hackers] Segfaults in ntp-dev
David L. Mills
mills at udel.edu
Sun Jun 3 13:33:55 PDT 2007
Guys,
The ntp-dev version has two known segfaults, maybe more. The fudge ...
time1 command segfaults in line 310 of ntp_config.c, but I can't find
anything wrong by looking at variables and pointers. I have a suspicion
though, and I'd like to ask for expert opinion.
A number of routines in Sachin's code declare a structure and return a
pointer to it. Obviously, the compiler can't put this on the stack, as
would ordinarily be the case. I would assume the compiler recognizes
this case in context and puts the structure on the heap. This makes me
nervous.
When I taught programming languages in a previous life, dumb compilers
insisted local declarations be on the stack, so Sachin's style was
forbidden. My preferred style is to declare a local pointer, malloc the
structure (on the heap), set the local pointer to the structure and
return the local pointer. Machines of the day returned values in the AC
and MQ 36-bit registers and had only three index registers.
My question is, am I a wuss or a wise man?
Dave
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