Subject: fresh-auto-compile doesn’t invalidate the compilation cache
From: [email-masked] (Ludovic Courtès)
To: [email-masked]
Date: Thu, 09 Nov 2017 13:53:22 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Hello,

‘%fresh-auto-compile’ is documented as a way to “forcibly invalidate the
auto-compilation cache” (info "(guile) Compilation"), but it seems that
it doesn’t invalidate much.  Specifically, ‘primitive-load-path’ does:

  compiled_thunk = load_thunk_from_path (filename, full_filename, &stat_source,
                                         &found_stale_compiled_file);

  if (scm_is_false (compiled_thunk)
      && scm_is_false (*scm_loc_fresh_auto_compile)
      …)
    { … }

  …

  if (scm_is_true (compiled_thunk))
    return scm_call_0 (compiled_thunk);
  else
    {
      SCM freshly_compiled = scm_try_auto_compile (full_filename);
      …
    }

So if there’s a .go file in the search path, it is *always* loaded, and
there’s no way we reach ‘scm_try_auto_compile’.

‘load-absolute’ in boot-9.scm seems to have the same problem:

  (and scmstat (or (pre-compiled) (fallback)))

I believe the attached patch fixes it.

Thoughts?

Thanks,
Ludo’.

diff --git a/libguile/load.c b/libguile/load.c
index 7b8136af8..3747dd9ad 100644
--- a/libguile/load.c
+++ b/libguile/load.c
@@ -1,5 +1,5 @@
 /* Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2004, 2006, 2008,
- *   2009, 2010, 2011, 2012, 2013, 2014 Free Software Foundation, Inc.
+ *   2009, 2010, 2011, 2012, 2013, 2014, 2017 Free Software Foundation, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public License
@@ -1195,13 +1195,16 @@ SCM_DEFINE (scm_primitive_load_path, "primitive-load-path", 0, 0, 1,
                                *scm_loc_load_extensions, SCM_BOOL_F,
                                &stat_source);
 
-  compiled_thunk = load_thunk_from_path (filename, full_filename, &stat_source,
-                                         &found_stale_compiled_file);
+  if (scm_is_false (*scm_loc_fresh_auto_compile))
+    compiled_thunk = load_thunk_from_path (filename, full_filename,
+					   &stat_source,
+					   &found_stale_compiled_file);
+  else
+    compiled_thunk = SCM_BOOL_F;
 
   if (scm_is_false (compiled_thunk)
       && scm_is_true (full_filename)
       && scm_is_true (*scm_loc_compile_fallback_path)
-      && scm_is_false (*scm_loc_fresh_auto_compile)
       && scm_is_pair (*scm_loc_load_compiled_extensions)
       && scm_is_string (scm_car (*scm_loc_load_compiled_extensions)))
     {
diff --git a/module/ice-9/boot-9.scm b/module/ice-9/boot-9.scm
index 7127d73f7..612040aa4 100644
--- a/module/ice-9/boot-9.scm
+++ b/module/ice-9/boot-9.scm
@@ -3812,7 +3812,10 @@ when none is available, reading FILE-NAME with READER."
                                               scmstat
                                               go-file-name))))))
 
-    (let ((compiled (and scmstat (or (pre-compiled) (fallback)))))
+    (let ((compiled (and scmstat
+                         (or (and (not %fresh-auto-compile)
+                                  (pre-compiled))
+                             (fallback)))))
       (if compiled
           (begin
             (if %load-hook