From 4c825252ed85c8ebeeb980e540ef3a6bdfb718d8 Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Wed, 11 Oct 2023 18:03:20 -0400
Subject: [PATCH] xo-cmake: + xo_add_headeronly_library()

---
 cmake/xo_cxx.cmake | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/cmake/xo_cxx.cmake b/cmake/xo_cxx.cmake
index f0e2e29b..13ee6b9a 100644
--- a/cmake/xo_cxx.cmake
+++ b/cmake/xo_cxx.cmake
@@ -108,6 +108,14 @@ macro(xo_add_shared_library target targetversion soversion sources)
     xo_install_library2(${target})
 endmacro()
 
+# ----------------------------------------------------------------
+# use this for a header-only library
+#
+macro(xo_add_headeronly_library target)
+    add_library(${target} INTERFACE)
+    xo_include_headeronly_options2(${target})
+endmacro()
+
 # ----------------------------------------------------------------
 # use this in subdirs that compile c++ code.
 # do not use for header-only subsystems;  see xo_include_headeronly_options2()