From 08d2d6cb00633760d5c4ee6e685facef70d82469 Mon Sep 17 00:00:00 2001
From: Gabriel Ferreira <gabrielcarvfer@gmail.com>
Date: Tue, 14 Jun 2022 15:08:41 -0300
Subject: [PATCH] build: widen find_external_library header search scope

---
 build-support/macros-and-definitions.cmake | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/build-support/macros-and-definitions.cmake b/build-support/macros-and-definitions.cmake
index 6141a887c..d816aeb68 100644
--- a/build-support/macros-and-definitions.cmake
+++ b/build-support/macros-and-definitions.cmake
@@ -1960,18 +1960,13 @@ function(find_external_library)
     list(APPEND parent_dirs ${libdir} ${parent_libdir} ${parent_parent_libdir})
   endforeach()
 
-  # If we already found a library somewhere, limit the search paths for the
-  # header
-  if(parent_dirs)
-    set(header_search_paths ${parent_dirs})
-    set(header_skip_system_prefix NO_CMAKE_SYSTEM_PATH)
-  else()
-    set(header_search_paths
-        ${search_paths} ${CMAKE_OUTPUT_DIRECTORY} # Search for headers in
-                                                  # ns-3-dev/build
-        ${CMAKE_INSTALL_PREFIX} # Search for headers in the install
-    )
-  endif()
+  set(header_search_paths
+      ${parent_dirs}
+      ${search_paths}
+      ${CMAKE_OUTPUT_DIRECTORY} # Search for headers in
+      # ns-3-dev/build
+      ${CMAKE_INSTALL_PREFIX} # Search for headers in the install
+  )
 
   set(not_found_headers)
   set(include_dirs)