Author: Florian Weimer <fweimer@redhat.com>
Date:   Tue Dec 19 11:00:11 2023 +0100

    configure: Only text the makecontext signature we need
    
    The test/explicit-bzero.c test uses a start routine without any
    arguments.  There is no need for the multi-argument version.
    
    This avoids a build failure with glibc and future compilers.
    The GNU C library declares the makecontext callback of
    type void (*) (void), so no cast is needed.  On other systems,
    the type may be the (currently distinct) type void (*) (),
    but given that this only affects the ability to execute a test,
    no further machinery is added here to detect that different type.

Submitted upstream: <https://github.com/besser82/libxcrypt/pull/178>

diff --git a/configure.ac b/configure.ac
index 35965b3b20466f71..ecc71b02b8c9752f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -303,13 +303,11 @@ AS_IF([test $ac_cv_header_ucontext_h = yes],
 #include <ucontext.h>
 static int x;
 static void fn1(void) {}
-static void fn2(int a, int b) { x = a - b; }
 ]], [[
   ucontext_t uc1, uc2;
   if (getcontext(&uc1)) return 1;
   if (setcontext(&uc1)) return 1;
   makecontext(&uc1, fn1, 0);
-  makecontext(&uc2, fn2, 2, 1, 1);
   if (swapcontext(&uc1, &uc2)) return 1;
   return x;
 ]])],