some automake installations might need this

adc10445 · Rob Latham · c7627745 · adc10445
Commit adc10445 authored Aug 28, 2017 by Rob Latham
--- a/configure.ac
+++ b/configure.ac
@@ -11,6 +11,8 @@ LT_PREREQ([2.2])
 # LT_INIT needs to know about AR
 AM_PROG_AR
 LT_INIT([dlopen])
+# subdir objects needs a bit of help
+AM_PROG_CC_C_O

 # Checks for programs.
 AC_PROG_CC