commit 5b9c0d01c638a789e4ffb7a6ab47e553cbb66923
Author: Daniel Swanson <popcorn.tomato.dude@gmail.com>
Date:   Tue Aug 3 11:29:44 2021 -0500

    check for string_view.h in order to properly link against lttoolbox

diff --git a/configure.ac b/configure.ac
index 335bbc1..1e81949 100644
--- a/configure.ac
+++ b/configure.ac
@@ -23,6 +23,8 @@ PKG_CHECK_MODULES([ICU], [icu-i18n icu-io icu-uc])
 AC_SUBST(ICU_CFLAGS)
 AC_SUBST(ICU_LIBS)
 
+AC_CHECK_HEADERS([string_view])
+
 CPPFLAGS="$CPPFLAGS $CFLAGS $LTTOOLBOX_CFLAGS $LIBXML_CFLAGS $ICU_CFLAGS"
 LIBS="$LIBS $LTTOOLBOX_LIBS $LIBXML_LIBS $ICU_LIBS"