ISO C

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* Implementations are "encouraged to ensure that representation of C and C++ atomic types is the same."

==Aliasing==

==Asserts==

* <tt>_Static_assert()</tt> is evaluated at compile time, huzzah!

==Generic dispatch==

The new <tt>_Genetic</tt> keyword allows mapping the type of an expression to a set of expressions. This is mainly usable for type-based dispatch of the kind seen in <tt>tgmath.h</tt>. You can't, so far as I can tell, use it for true parametric polymorphism. Tony Finch demonstrates a clever use for [https://fanf.livejournal.com/144696.html parametric constness]:

<code>

#define strchr(s,c) _Generic((s), \

const char * : (const char *)(strchr)((s), (c)), \

char * : (strchr)((s), (c)))</code>

==Types==

===Aliasing===

* See [[Compiler Design]] page

* -O2 implies -fstrict-aliasing, at least as of gcc 4.3

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** How to use Berkeley sockets API? See http://archives.free.net.ph/message/20080529.200047.b40321b6.fi.html, etc

~~==Types==~~

===stdint.h===

An excellent addition in C99. Type constructions of the form u?int{variety}_t (u prefix denotes unsigned). Varieties include:

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* <tt>least{8,16,32,64}</tt>: Minimum native integer type having at least the specified width.

* <tt>{8,16,32,64}</tt>: Integer type having precisely this width.

====inttypes.h====

ugly <tt>printf</tt> specifiers for the types in <tt>stdint.h</tt>. e.g.:

* <tt>printf("%"PRIu64"\n", some_uint64_tvar);</tt>

===tgmath.h===

~~===_Generic===~~

C11 introduced the new keyword <tt>[https://en.cppreference.com/w/c/language/generic _Generic]</tt>, allowing one of several type-tagged expressions to be chosen based on the type of a controlling expression.

===<tt>static</tt> in array parameters===

Beginning with C99, <tt>static</tt> can be inserted into array parameters ala:

ISO C: Difference between revisions

Dank (talk | contribs)

@@ Line 15: / Line 15: @@
 * Implementations are "encouraged to ensure that representation of C and C++ atomic types is the same."
-==Aliasing==
+==Asserts==
+* <tt>_Static_assert()</tt> is evaluated at compile time, huzzah!
+==Generic dispatch==
+The new <tt>_Genetic</tt> keyword allows mapping the type of an expression to a set of expressions. This is mainly usable for type-based dispatch of the kind seen in <tt>tgmath.h</tt>. You can't, so far as I can tell, use it for true parametric polymorphism. Tony Finch demonstrates a clever use for [https://fanf.livejournal.com/144696.html parametric constness]:
+<code>
+    #define strchr(s,c) _Generic((s),                    \
+        const char * : (const char *)(strchr)((s), (c)), \
+        char *       :               (strchr)((s), (c)))</code>
+==Types==
+===Aliasing===
 * See [[Compiler Design]] page
 * -O2 implies -fstrict-aliasing, at least as of gcc 4.3
@@ Line 21: / Line 32: @@
 ** How to use Berkeley sockets API? See http://archives.free.net.ph/message/20080529.200047.b40321b6.fi.html, etc
-==Types==
 ===stdint.h===
 An excellent addition in C99. Type constructions of the form u?int{variety}_t (u prefix denotes unsigned). Varieties include:
@@ Line 29: / Line 40: @@
 * <tt>least{8,16,32,64}</tt>: Minimum native integer type having at least the specified width.
 * <tt>{8,16,32,64}</tt>: Integer type having precisely this width.
+====inttypes.h====
+ugly <tt>printf</tt> specifiers for the types in <tt>stdint.h</tt>. e.g.:
+* <tt>printf("%"PRIu64"\n", some_uint64_tvar);</tt>
 ===tgmath.h===
-===_Generic===
-C11 introduced the new keyword <tt>[https://en.cppreference.com/w/c/language/generic _Generic]</tt>, allowing one of several type-tagged expressions to be chosen based on the type of a controlling expression.
 ===<tt>static</tt> in array parameters===
 Beginning with C99, <tt>static</tt> can be inserted into array parameters ala: