backend/ninja: fortran must fully depend on all linked targets

Because we use this dependency to ensure that any binary module files
are generated, we must have a full dependency. Otherwise, if a new
module is added to a dependent target, and used in our target, we race
the generation of the binary module definition.

1 files changed, 7 insertions, 5 deletions

diff --git a/mesonbuild/backend/ninjabackend.py b/mesonbuild/backend/ninjabackend.py
index 2faf8c1d3..b28bec34b 100644
--- a/mesonbuild/backend/ninjabackend.py
+++ b/mesonbuild/backend/ninjabackend.py
@@ -3144,8 +3144,8 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
                 d = os.path.join(self.get_target_private_dir(target), d)
             element.add_orderdep(d)
         element.add_dep(pch_dep)
-        for i in self.get_fortran_orderdeps(target, compiler):
-            element.add_orderdep(i)
+        for i in self.get_fortran_module_deps(target, compiler):
+            element.add_dep(i)
         if dep_file:
             element.add_item('DEPFILE', dep_file)
         if compiler.get_language() == 'cuda':
@@ -3212,10 +3212,12 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
     # Fortran is a bit weird (again). When you link against a library, just compiling a source file
     # requires the mod files that are output when single files are built. To do this right we would need to
     # scan all inputs and write out explicit deps for each file. That is too slow and too much effort so
-    # instead just have an ordered dependency on the library. This ensures all required mod files are created.
+    # instead just have a full dependency on the library. This ensures all required mod files are created.
     # The real deps are then detected via dep file generation from the compiler. This breaks on compilers that
-    # produce incorrect dep files but such is life.
-    def get_fortran_orderdeps(self, target, compiler):
+    # produce incorrect dep files but such is life. A full dependency is
+    # required to ensure that if a new module is added to an existing file that
+    # we correctly rebuild.
+    def get_fortran_module_deps(self, target, compiler) -> T.List[str]:
         if compiler.language != 'fortran':
             return []
         return [