git: 02b0d4b688cc - main - sys/cdefs.h: add __noexcept and __noexcept_if

From: Warner Losh <imp_at_FreeBSD.org>
Date: Fri, 02 Feb 2024 18:16:58 UTC
The branch main has been updated by imp:

URL: https://cgit.FreeBSD.org/src/commit/?id=02b0d4b688cc4deb14cb6e7534a2a4958e48b753

commit 02b0d4b688cc4deb14cb6e7534a2a4958e48b753
Author:     Lexi Winter <lexi@le-Fay.ORG>
AuthorDate: 2024-02-02 16:41:40 +0000
Commit:     Warner Losh <imp@FreeBSD.org>
CommitDate: 2024-02-02 18:11:17 +0000

    sys/cdefs.h: add __noexcept and __noexcept_if
    
    These macros provide the C++11 noexcept and noexcept(...) keywords if
    we're compiling in a C++11 environment.  Otherwise, they expand to an
    empty string.
    
    This will be used to add the required noexcept specifier to several libc
    functions as required in C++11.
    
    MFC after:      2 weeks
    
    Reviewed by: imp
    Pull Request: https://github.com/freebsd/freebsd-src/pull/1085
---
 sys/sys/cdefs.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/sys/sys/cdefs.h b/sys/sys/cdefs.h
index fcc90b4d8aee..206cc569c55a 100644
--- a/sys/sys/cdefs.h
+++ b/sys/sys/cdefs.h
@@ -358,6 +358,17 @@
 #endif
 #endif
 
+/*
+ * noexcept keyword added in C++11.
+ */
+#if defined(__cplusplus) && __cplusplus >= 201103L
+#define __noexcept noexcept
+#define __noexcept_if(__c) noexcept(__c)
+#else
+#define __noexcept
+#define __noexcept_if(__c)
+#endif
+
 /*
  * We use `__restrict' as a way to define the `restrict' type qualifier
  * without disturbing older software that is unaware of C99 keywords.