Hi, Googling around, you will find many people saying that C99 disallows undefined functions (e.g [1]), often citing C99 6.5.2.2. My reading of this doesn't seem to suggest it disallows undefined functions; in fact it talks about type promotion rules for undefined functions. And indeed, even with -std=c99 gcc still only warns about undefined functions (and assumes they return int, etc), not gives an error. This is particularly annoying on 64 bit architectures where the top bits of pointers get stripped when converted to int when people forget to include the right headers. A compiler error (yes it warns, but people often ignore it) rather than a segfault would be more useful. Can anyone point me to where C99 explicitly disallows a function without a declaration, and if so why doesn't gcc in C99 mode give an error rather than falling back to the C89 semantics? Or are the numerous people suggesting C99 disallows undefined functions incorrect? -i ianw@xxxxxxxxxxxxxxxxxx http://www.gelato.unsw.edu.au [1] http://david.tribble.com/text/cdiffs.htm ("Implicit function declarations")
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