Questions tagged [c23]
C23 is the informal name of the next standard of the C programming language. It replaces C17 and introduces some new features.
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Is it considered normal that f = NAN may cause raising floating-point exceptions?
C2x (as well as previous):
The macro NAN is defined if and only if the implementation supports quiet NaNs for the float type. It expands to a constant expression of type float representing a quiet ...
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What is the definition of a "valid program"?
ISO/IEC 9899:202x (E) working draft — December 11, 2020 N2596, footnote 9:
... an implementation is free to produce any number of diagnostic messages, often referred to as warnings, as long as a ...
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C2x: 6.9.2 External object definitions: why is "shall not be an incomplete type" placed in Semantics rather than in Constraints?
Follow-up question for: What is the rationale for "semantics violation does not require diagnostics"?.
N2596 working draft — December 11, 2020 ISO/IEC 9899:202x (E), 6.9.2 External object ...
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Is [[nodiscard]] any different from [[gnu::warn_unused_result]]?
I had some code that used the GCC extension [[gnu::warn_unused_result]] (a.k.a. __attribute__((__warn_unused_result__))). Now I attempted to use C2x's [[nodiscard]] and I got an incomprehensible ...
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Is there a char8_t in C?
I have searched in many sites and did not get anything. I know that char8_t is a keyword in C++ since C++20. I am trying to find out in C, are they typedef-ing unsigned char to char8_t in C23 (with ...
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What's the point of the __unused attribute in C?
I've got a question. Let's say you define a function or variable in C. If you don't use it, the compiler generates a warning that this variable/function wasn't used. To suppress the warning, you use ...
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