Re: Missing '_Noreturn'

[Paul Eggert]

On 7/26/20 3:10 PM, Gisle Vanem wrote:
> Here's an error though:
>
>    test-dfa-match-aux.c
>    test-dfa-match-aux.c(39): error C2381: 'dfawarn': redefinition;
>    '__declspec(noreturn)' or '[[noreturn]]' differs
>    lib\dfa.h(125): note: see declaration of 'dfawarn'

That's a bug in MSVC. _Noreturn and 'inline' are not part of a function's type, 
so the definition of a function can say '_Noreturn' even though its declaration 
does not. (Admittedly it's bad style.)

> -extern void dfawarn (const char *);
> +extern _Noreturn void dfawarn (const char *);

That can't be right, as dfawarn typically does return.

Does the following work around the compiler bug? If not we can use stronger 
medicine.

diff --git a/tests/test-dfa-match-aux.c b/tests/test-dfa-match-aux.c
index e0c5f3df4..167b0ef8b 100644
--- a/tests/test-dfa-match-aux.c
+++ b/tests/test-dfa-match-aux.c
@@ -28,6 +28,9 @@

 #include "getprogname.h"

+_Noreturn void dfaerror (char const *);
+_Noreturn void dfawarn (char const *);
+
 _Noreturn void
 dfaerror (char const *mesg)
 {