321–330 of 978 posts
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Yes, the C2x charter has this requirement: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2086.htm
Thanks, so from "Only those features that have a history and are in common use by a commercial implementation should be considered", this precludes stuff that may only exist in clang, gcc, glibc, etc.? If so, why?
As there are a lot of C-masters lurking in this thread: How can one process unicode (UTF-8) properly in C? As a CJK person, I wish there was a robust solution. Are there any standardized ways or proposals? (Using wchar doesn't count.)
However, the book only describes the available standard functions, so even doing better than other manuals, everything it has to say on this subject fits in one chapter and feel underpowered.
What's the best way to deal with "transitive const-ness", i.e. utility functions that operate on pointers and where the return type should technically get const from the argument? (strchr is the most obvious, but in general most search/lookup type functions are like this...) Add to clarify: the current prototype for strchr is char *strchr(const char *s, int c); Which just drops the "const", so you might end up writin…
I appreciate the original simplicity of K & R, "The C Programming Language", 2nd Edition, and the relatively simple semantics of ANSI C89/ISO C90 compared to C99 and later.
You don't need complex parsing methods for ANSI C89/ISO C90 and you do not need the "lexer hack" to handle the typedef-name versus other "ordinary identifier" ambiguity.
A surprising number of colleges still teach K & R 2nd Edition C.
Whenever someone brags about using recursive-descent parsing methods, I always ask, are they using predictive, top-down parsing, or back-tracking?
I hope C never loses sight of it's roots nor morphs into C++ under the guise of creating a common subset, but which is really a disguised superset of C and C++
Please prevent the ever increasing demand for new features from overwhelming C's simplicity so it can no longer be parsed with simple methods.
I'm teaching C to high schoolers as their first language, which is quite the adventure. Do you have any good advice or resources on how to introduce the way C treats the function stack and heap allocated memory? Most of my students struggle (naturally) with making sense of function scoped identifiers and pass-by-value semantics.
Have you given ada language a thought ? Also there are lot of competition your students can take part in https://www.makewithada.org/
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> Proper array support (which passes around the length along with the data pointer). I second this one. One of the best things from Rust is its "fat pointers", which combine a (pointer, length) or a (pointer, vtable) pair as a single unit. When you pass an array or string slice to a function, under the covers the Rust compiler passes a pair of arguments, but to the programmer they act as if they were a single thing (…
Fat pointers in C would involve an ABI break for existing code, in that uintptr_t and uintmax_t would probably need to double in size.
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I think we are always looking at ways to "clean up C" but that this has to be done very carefully not to break existing code. For example, the committee recently voted to remove support for function definitions with identifier lists from C2x http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2432.pdf At least one vendor was not very happy with this decision. Undefined behaviors tend to be undefined for a reason and sho…
Does it concern you how aggressively compiler teams are exploiting UB?
For example, consider a very simple statement.
let array[10];
let i = some_function();
print(array[i]);
But the compiler is like "hey! you used the result of this function as an index for this array! i must be in the range [0, 10)! I can use that information!"
By passing -Wl,--wrap=some_function at link time with test code we can then define
__wrap_some_function
Do you have any other recommendations/preferences to help with unit-testing C code?
Cheers from the shadowland :)