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Ticket UUID:	04aad56155f0546ddaaa2aaa66106f1b3057eeae
Title:	__attribute__((noreturn)) conflicts with stdnoreturn.h
Type:	Patch	Version:	8.6.16, 9.0.1
Submitter:	petere	Created on:	2025-04-07 08:09:13
Subsystem:	50. Embedding Support	Assigned To:	jan.nijtmans
Priority:	5 Medium	Severity:	Minor
Status:	Closed	Last Modified:	2025-04-07 09:49:58
Resolution:	Fixed	Closed By:	jan.nijtmans
		Closed on:	2025-04-07 09:49:58
Description:	If `<stdnoreturn.h>` is included first, then `noreturn` is defined to `_Noreturn`, and then `__attribute__((noreturn))` will end up being `__attribute__((_Noreturn))`, which would not be recognized and might result in a compiler warning. To avoid this, use the alternative spelling `__attribute__((__noreturn__))` instead. This is supported by the same compiler versions. But I don't know if there is an equivalent workaround for `__declspec(noreturn)`. An alternative might be to do `#define TCL_NORETURN _Noreturn` if the compiler is in C11 mode.
User Comments:	jan.nijtmans added on 2025-04-07 09:49:58: Thanks for the report. Fixed [4dccf561263d0f83\|here] Since <stdnoreturn.h> has issues on various platforms, and _Noreturn is already deprecated in C23, I recommend not to use `<stdnoreturn.h>`. But since the double-underscored variants give less chance to problems, your suggestion is better than doing nothing. See: https://www.gnu.org/software/gnulib/manual/html_node/stdnoreturn_002eh.html Thanks!

Attachments:

0001-Fix-potential-conflict-of-__attribute__-noreturn.patch [download] added by petere on 2025-04-07 08:09:52. [details]