Re: GLR causing warning about _Noreturn in C99

[Akim Demaille]

Hi Joe,

> Le 12 janv. 2021 à 00:59, Joe Nelson <joe@begriffs.com> a écrit :
> 
> Joe Nelson wrote:
>> Ah, in that case I'll report the bug upstream in gnulib. When they fix
>> it we can copy their updated code.
> 
> OK, they fixed the bug in gnulib:
> 
> https://git.savannah.gnu.org/gitweb/?p=gnulib.git;a=commit;h=077ffc1e416a6be980dd45979547201e572962f6
> 
> Here's the updated _Noreturn.h (notice how they now check
> __STRICT_ANSI__):
> 
> https://git.savannah.gnu.org/gitweb/?p=gnulib.git;a=blob;f=lib/_Noreturn.h;h=cb72f2620604406c9552d7bb5f8ffe578a3aadef;hb=077ffc1e416a6be980dd45979547201e572962f6

I adjusted this patch for Bison.  Could you please try this tarball before I 
install the appended patch into master?  Thanks in advance.

Cheers!

https://www.lrde.epita.fr/~akim/private/bison/bison-3.7.4.256-1c00e.tar.gz
https://www.lrde.epita.fr/~akim/private/bison/bison-3.7.4.256-1c00e.tar.lz
https://www.lrde.epita.fr/~akim/private/bison/bison-3.7.4.256-1c00e.tar.xz


commit e70df34a35e2548d76ee0ab3f548ccb45fcc3253
Author: Akim Demaille <akim.demaille@gmail.com>
Date:   Tue Jan 12 06:28:13 2021 +0100

    c: adjust _Noreturn to pedantic clang
    
    Reported by Joe Nelson <joe@begriffs.com>.
    https://lists.gnu.org/r/help-bison/2021-01/msg00004.html
    Fixed by Paul Eggert in gnulib.
    https://lists.gnu.org/r/bug-gnulib/2021-01/msg00156.html
    
    * data/skeletons/c.m4 (b4_attribute_define): Adjust _Noreturn to
    pedantic clang.

diff --git a/data/skeletons/c.m4 b/data/skeletons/c.m4
index ed2c762c..4391dbc2 100644
--- a/data/skeletons/c.m4
+++ b/data/skeletons/c.m4
@@ -378,14 +378,16 @@ dnl use C' _Noreturn in C++, to avoid -Wc11-extensions 
warnings.
       && ((201103 <= __cplusplus && !(__GNUC__ == 4 && __GNUC_MINOR__ == 7)) \
           || (defined _MSC_VER && 1900 <= _MSC_VER)))
 #  define _Noreturn [[noreturn]]
-# elif (!defined __cplusplus                     \
-        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0)  \
-            || 4 < __GNUC__ + (7 <= __GNUC_MINOR__) \
-            || (defined __apple_build_version__ \
-                ? 6000000 <= __apple_build_version__ \
-                : 3 < __clang_major__ + (5 <= __clang_minor__))))
+# elif ((!defined __cplusplus || defined __clang__) \
+        && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) \
+            || (!defined __STRICT_ANSI__ \
+                && (__4 < __GNUC__ + (7 <= __GNUC_MINOR__) \
+                    || (defined __apple_build_version__ \
+                        ? 6000000 <= __apple_build_version__ \
+                        : 3 < __clang_major__ + (5 <= __clang_minor__))))))
    /* _Noreturn works as-is.  */
-# elif 2 < __GNUC__ + (8 <= __GNUC_MINOR__) || 0x5110 <= __SUNPRO_C
+# elif (2 < __GNUC__ + (8 <= __GNUC_MINOR__) || defined __clang__ \
+        || 0x5110 <= __SUNPRO_C)
 #  define _Noreturn __attribute__ ((__noreturn__))
 # elif 1200 <= (defined _MSC_VER ? _MSC_VER : 0)
 #  define _Noreturn __declspec (noreturn)