Language in thought and action or "what's correct vs. what's right"
Everybody should IMO, at some point of his life, have read Hayakawa's "Language in thought and action". It is a book about semantics, of words and their meanings. Semantics pop up in very amusing situations, for example in code analysis/review, and a few other places.
A small thing to take out of that book is that the entry in a dictionary is not the definitive meaning of a word, but that the meaning of the word is (somewhat circularly) defined as what the collective mind thinks this word means.
There's currently an bugtraq about the way that GCC treats certain 'invalid language' constructs. While I find very few things more amusing than compiler changes breaking formerly working code, I also find the reaction of everybody except fefe on that list to be very amusing: Instead of relying on what everybody thinks the meaning of that line of code is, they refer to the written standard. In essence, they look up the meaning of a word in a dictionary.
Yes, standards are important. But there is a difference between the standard on paper and the 'standard', meaning the way everybody perceives (and writes in) that language. And due to the fact that C's standard has been in some ways unenforced for 20+ years there are lots of existing 'standard' idioms (such as Fefe's int wrap check) that are not valid by the written standard.
What we're trying to do here is the equivalent of not correcting a child's grammar for 20 years, allowing it to play with other kids with broken grammar and always understanding what the child wanted to say when it used broken grammar. And then, once it turned 20, we cross out the constructs with bad grammar from everything he says and interpret the rest.
If the construct is so invalid, have the compiler warn at least :)
This sounds like a sure recipe for disaster to me :)
I had a discussion with Rolf yesterday about GCC's ghastlyness, and the fact that we're spending a good bit of our time fighting compiler woes instead of coding. Then again, we're doing something rather odd: We're trying to write C++ code with GCC, which frankly, doesn't work. I am very inclined to switch to Intel's CPP.
Oh, while I am at ranting: On which CPU is GCC's weird optimization of passing arguments by subtracting from ESP and then issuing several 'mov [esp+const], reg' faster than push/call ? Sure, on a cycle-by-cycle basis each instruction is faster, but has anyone ever considered the impact of a 3*size increase in the code on CPU caching ?
I'll shut up now before this deteriorates into more ranting.
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