Index: zvbi-0.2.42/configure.ac
===================================================================
--- zvbi-0.2.42.orig/configure.ac
+++ zvbi-0.2.42/configure.ac
@@ -82,7 +82,7 @@ AC_CHECK_FUNCS([alarm dup2 gethostbyaddr
 		inet_ntoa localtime_r memmove memset mkdir modf munmap
 		nl_langinfo putenv select setenv setlocale socket strcasecmp
 		strchr strdup strerror strncasecmp strndup strrchr strstr
-		strtol strtoul tzset strptime getaddrinfo])
+		strtol strtoul tzset strptime getaddrinfo sincos])
 
 AM_CONDITIONAL(HAVE_STRPTIME, [test "x$HAVE_STRPTIME" = xyes])
 
@@ -105,28 +105,6 @@ dnl autoconf 2.71 required additional qu
 dnl "Noteworthy changes in autoconf version 2.66 through 2.68"
 dnl <https://autotools.info/forwardporting/autoconf.html>
 
-dnl sincos() is a GNU extension (a macro, not a function).
-dnl If not present we use a replacement.
-AC_MSG_CHECKING([for sincos])
-AC_LINK_IFELSE([AC_LANG_SOURCE([
-#include <stdio.h>
-#include <math.h>
-int main (void) {
-double s, c;
-/* Make sure the compiler does not optimize sincos() away
-   so the linker can confirm its availability. */
-scanf ("%f", &s);
-sincos (s, &s, &c);
-printf ("%f %f", s, c);
-return 0;
-}
-])],[
-  AC_MSG_RESULT([yes])
-  AC_DEFINE(HAVE_SINCOS, 1, [Define if the sincos() function is available])
-],[
-  AC_MSG_RESULT([no])
-])
-
 dnl log2() is a GNU extension (a macro, not a function).
 dnl If not present we use a replacement.
 AC_MSG_CHECKING([for log2])