From 2fbc857ff4592b55acb8f4788d39c9f0fa0928dd Mon Sep 17 00:00:00 2001
From: Jussi Pakkanen <jpakkane@gmail.com>
Date: Sun, 8 Oct 2017 17:11:29 +0300
Subject: [PATCH] Better error message when using external libraries
 incorrectly. Closes #2447.

---
 mesonbuild/build.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/mesonbuild/build.py b/mesonbuild/build.py
index 9837d5a8d..2a71b8b4b 100644
--- a/mesonbuild/build.py
+++ b/mesonbuild/build.py
@@ -640,6 +640,12 @@ class BuildTarget(Target):
             # in kwargs. Unpack here without looking at the exact type.
             if hasattr(linktarget, "held_object"):
                 linktarget = linktarget.held_object
+            if isinstance(linktarget, dependencies.ExternalLibrary):
+                raise MesonException('''An external library was used in link_with keyword argument, which
+is reserved for libraries built as part of this project. External
+libraries must be passed using the dependencies keyword argument
+instead, because they are conceptually "external dependencies",
+just like those detected with the dependency() function.''')
             self.link(linktarget)
         lwhole = extract_as_list(kwargs, 'link_whole')
         for linktarget in lwhole: