This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 115d. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2024-10-26

2144. Function/variable declaration ambiguity

Section: 9.5.1  [dcl.fct.def.general]     Status: DR     Submitter: Richard Smith     Date: 2015-06-19

[Accepted as a DR at the June, 2024 meeting.]

The following fragment,

  int f() {};

is syntactically ambiguous. It could be either a function-definition followed by an empty-declaration, or it could be a simple-declaration whose init-declarator has the brace-or-equal-initializer {}. The same is true of a variable declaration

  int a {};

since function-definition simply uses the term declarator in its production.

Additional notes (May, 2024)

Issue 2876 introduced a framework to distinguish the parsing. Its resolution was extended to also resolve this issue.