What is C17 and what changes have been made to the language?

Question

As I was checking news about GCC 8, I saw that they added support for the 2017 version of the C language (not C++17, really C17). But I can\'t find any information about it on I

Answer 1

C17 is a “bugfix release” of the C standard how "M.S Chaudhari" noticed. However, there is very useful information prepared by Jens Gustedt the author of "Modern C" book.

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He identified the following list of changes in C17 compared to C11:

• atomics: initialization (7.17.2, 7.31.8), coherence requirements (5.1.2.4), fences (7.17.3 p11), functions or macros (7.17.1 p6), lockfree depends on type (7.17.5 p3), compare exchange compares memory and not value (7.17.7.3), atomic_flag (7.17.18).

• threads: spurious failures (7.26.3.5 p2, 7.26.3.6 p2, 7.26.4.5 p3), synchronization (7.26.4 p1), thread specific storage (tss_t) and thread exit (7.26.5 p3, 7.26.5.5, 7.26.6)

• _Generic (6.5.1.1), rvalues and qualification, cast (6.5.4)

• alignment: fundamental alignment (6.2.8), _Alignas (6.7.5), aligned_alloc (7.22.3.1)

• sequence points: full expressions (6.8 p4), full declarators (6.7..6 p3)

• infinite loops (6.8.5 p6)

• reserved identifiers (7.1.3)

• domain or range errors (7.12.1), ilogb, erfc, lgamma.

• underspecification of clock (7.27.2.1)

• underspecification of realloc for size 0 (7.22.3.5)

• Annex F: FLT_ROUNDS (F.2 p1)

• Annex K: tmpnam_s, snprintf_s, sprintf_s, vsprintf_s, get_s, mbstowcs_s, wcstombs_s, snwprintf_s, swprintf_s, vsnwprintf_s, vswprint_s, mbsrtowcs_s, wcsrtombs_s.

Link to the main page C17.

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Also, this content will be updated by Jens you can follow to update here Jeans Gustedt Blog.

P.S: before posting all this stuff I received approval from the author.