Update comments and docstrings

Author: JukkaL

mypyc/build.py

@@ -725,7 +725,6 @@ def mypycify(
             rt_file = os.path.join(build_dir, name)
             with open(os.path.join(include_dir(), name), encoding="utf-8") as f:
                 write_file(rt_file, f.read())
-            # Only add .c files to shared_cfilenames
             if name.endswith(".c"):
                 shared_cfilenames.append(rt_file)
 

mypyc/ir/deps.py

@@ -5,6 +5,7 @@ class Capsule:
     """Defines a C extension capsule that a primitive may require."""
 
     def __init__(self, name: str) -> None:
+        # Module fullname, e.g. 'librt.base64'
         self.name: Final = name
 
     def __repr__(self) -> str:
@@ -18,9 +19,14 @@ def __hash__(self) -> int:
 
 
 class SourceDep:
-    """Defines a C source file that a primitive may require."""
+    """Defines a C source file that a primitive may require.
+
+    Each source file must also have a corresponding .h file (replace .c with .h)
+    that gets implicitly #included if the source is used.
+    """
 
     def __init__(self, path: str) -> None:
+        # Relative path from mypyc/lib-rt, e.g. 'bytes_extra_ops.c'
         self.path: Final = path
 
     def __repr__(self) -> str: