At 08:27 AM 1/29/2003 -0600, Alif The Terrible wrote:
FORTRAN/COBOL array bounds checking. Bell Labs answer: C. Who wants the computer to check array lengths or pointers. Programmers know what they are doing, and don't need to be "constrained" by the programming language. Everyone knows programmers are better at arithmatic than computers. A programmer would never make an off-by-one error. The standard C run-time library. gets(char *buffer), strcpy(char *dest, char *src), what were they thinking?
Possibly that bounds checking is an incredible cpu suck
It doesn't have to be, if your compiler is worth its salt. Take a look at the GNU Ada compiler implementation of bound checking -- incredibly efficient. There are optimizations and inductive reasoning you can perform at compile time. Strongly typed programming languages make it easier to perform those optimizations, which is a major problem for C (everything's a pointer, right? :-) However, the current language fad is Java, which is somewhat more strongly typed.
, there are a great
many powerful things you can do in C based on the fact that there is no bounds checking (pointers ARE your friend god damnit :P), and in a world before buffer overflow exploits it probably didn't matter if Joe Idiot's program crashed because he goofed? (hindsight is 20/20)
Not sure if this was ever true for networked applications. The original Morris ARPANet worm exploited a buffer overrun vulnerability in the BSD Unix finger daemon. There's no excuse for failing to change behavior, or not re-visiting bounds checking in compilers & interpreters / virtual machines (e.g. JVM). Finally, and rather off-topic, I have yet to come across a C programming technique that "can't be done" efficiently in, say, Ada -- a language that usually gives C programmers fits of apoplexy. You just have to know how to express the solution in that language, rather than forcing a literal translation of the way it's done in C. Cheers, Mathew