custom target: Consider all build depends while serializing

Currently, we only consider the build depends of the Executable being
run when serializing custom targets. However, this is not always
sufficient, for example if the executable loads modules at runtime or if
the executable is actually a python script that loads a built module.

For these cases, we need to set PATH on Windows correctly or the custom
target will fail to run at build time complaining about missing DLLs.

1 files changed, 18 insertions, 12 deletions

diff --git a/mesonbuild/backend/backends.py b/mesonbuild/backend/backends.py
index d613f50..3e12c89 100644
--- a/mesonbuild/backend/backends.py
+++ b/mesonbuild/backend/backends.py
@@ -238,8 +238,14 @@ class Backend:
         return obj_list
 
     def serialize_executable(self, exe, cmd_args, workdir, env={},
-                             capture=None):
+                             extra_paths=None, capture=None):
         import hashlib
+        if extra_paths is None:
+            # The callee didn't check if we needed extra paths, so check it here
+            if mesonlib.is_windows() or mesonlib.is_cygwin():
+                extra_paths = self.determine_windows_extra_paths(exe, [])
+            else:
+                extra_paths = []
         # Can't just use exe.name here; it will likely be run more than once
         if isinstance(exe, (dependencies.ExternalProgram,
                             build.BuildTarget, build.CustomTarget)):
@@ -272,10 +278,6 @@ class Backend:
                 exe_wrapper = self.environment.cross_info.config['binaries'].get('exe_wrapper', None)
             else:
                 exe_wrapper = None
-            if mesonlib.is_windows() or mesonlib.is_cygwin():
-                extra_paths = self.determine_windows_extra_paths(exe)
-            else:
-                extra_paths = []
             es = ExecutableSerialisation(basename, exe_cmd, cmd_args, env,
                                          is_cross_built, exe_wrapper, workdir,
                                          extra_paths, capture)
@@ -529,23 +531,27 @@ class Backend:
             args.append(d_arg)
         return args
 
-    def determine_windows_extra_paths(self, target):
+    def determine_windows_extra_paths(self, target, extra_bdeps):
         '''On Windows there is no such thing as an rpath.
         We must determine all locations of DLLs that this exe
         links to and return them so they can be used in unit
         tests.'''
-        if not isinstance(target, build.Executable):
-            return []
-        prospectives = target.get_transitive_link_deps()
         result = []
+        prospectives = []
+        if isinstance(target, build.Executable):
+            prospectives = target.get_transitive_link_deps()
+            # External deps
+            for deppath in self.rpaths_for_bundled_shared_libraries(target):
+                result.append(os.path.normpath(os.path.join(self.environment.get_build_dir(), deppath)))
+        for bdep in extra_bdeps:
+            prospectives += bdep.get_transitive_link_deps()
+        # Internal deps
         for ld in prospectives:
             if ld == '' or ld == '.':
                 continue
             dirseg = os.path.join(self.environment.get_build_dir(), self.get_target_dir(ld))
             if dirseg not in result:
                 result.append(dirseg)
-        for deppath in self.rpaths_for_bundled_shared_libraries(target):
-            result.append(os.path.normpath(os.path.join(self.environment.get_build_dir(), deppath)))
         return result
 
     def write_benchmark_file(self, datafile):
@@ -576,7 +582,7 @@ class Backend:
             else:
                 exe_wrapper = None
             if mesonlib.is_windows() or mesonlib.is_cygwin():
-                extra_paths = self.determine_windows_extra_paths(exe)
+                extra_paths = self.determine_windows_extra_paths(exe, [])
             else:
                 extra_paths = []
             cmd_args = []