Issue #19922: define _INCLUDE__STDC_A1_SOURCE in HP-UX to include mbstate_t
for mbrtowc().
diff --git a/configure.ac b/configure.ac
index 14b3aef..2d701b1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -522,6 +522,13 @@
AC_DEFINE(_POSIX_C_SOURCE, 200809L, Define to activate features from IEEE Stds 1003.1-2008)
fi
+# On HP-UX mbstate_t requires _INCLUDE__STDC_A1_SOURCE
+case $ac_sys_system in
+hp*|HP*)
+ AC_DEFINE(_INCLUDE__STDC_A1_SOURCE, 1, Define to include mbstate_t for mbrtowc)
+ ;;
+esac
+
#
# SGI compilers allow the specification of the both the ABI and the
# ISA on the command line. Depending on the values of these switches,