Re: Define operator new/delete for smobs (issue 551390047 by address@hidden)

[hanwenn]

Reviewers: dak,

Message:
On 2020/01/25 12:37:32, dak wrote:
> That seems weird for me.  The topic states "this provides a way to run
LilyPond
> with Guile 2.2" but garbage collection with Guile 2.2 works out of the
box
> already.  This patch only causes extra work and will slow down garbage
> collection further.
> 
> The only way in which it could make sense is if in return some other
GC hooks
> and/or work would be disabled.

running against

$ guile2.2 --version
guile (GNU Guile) 2.2.4

I get 

Import (ice-9 threads) to have access to `call-with-new-thread'.
Import (ice-9 threads) to have access to `current-thread'.
Processing `input/regression/mozart-hrn-3.ly'
Parsing...double free or corruption (!prev)

Thread 5 "lilypond" received signal SIGABRT, Aborted.
[Switching to Thread 0x7fffeea92700 (LWP 31206)]
0x00007ffff7526e35 in raise () from /lib64/libc.so.6
Missing separate debuginfos, use: dnf debuginfo-install
guile22-2.2.4-3.fc30.x86_64 libunistring-0.9.10-5.fc30.x86_64
(gdb) up
#1  0x00007ffff7511895 in abort () from /lib64/libc.so.6
(gdb) 
#2  0x00007ffff756a08f in __libc_message () from /lib64/libc.so.6
(gdb) 
#3  0x00007ffff757140c in malloc_printerr () from /lib64/libc.so.6
(gdb) 
#4  0x00007ffff75731bc in _int_free () from /lib64/libc.so.6
(gdb) 
#5  0x00000000004dd2c4 in Simple_smob<Input>::free_smob (obj=<optimized
out>) at /usr/include/c++/9/bits/basic_string.h:2300
2300          c_str() const _GLIBCXX_NOEXCEPT
(gdb) 
#6  0x00007ffff7b8b4a5 in GC_invoke_finalizers () at finalize.c:1216
1216            (*(curr_fo -> fo_fn))((ptr_t)(curr_fo -> fo_hidden_base),
(gdb) down
#5  0x00000000004dd2c4 in Simple_smob<Input>::free_smob (obj=<optimized
out>) at /usr/include/c++/9/bits/basic_string.h:2300
2300          c_str() const _GLIBCXX_NOEXCEPT
(gdb) quit


Description:
Define operator new/delete for smobs

This marks the memory for tracing with BDW GC in GUILE >= 2.0
automatically. This provides a way to run LilyPond against GUILE 2.2.

Please review this at https://codereview.appspot.com/551390047/

Affected files (+9, -0 lines):
  M lily/include/smobs.hh


Index: lily/include/smobs.hh
diff --git a/lily/include/smobs.hh b/lily/include/smobs.hh
index 
5fd1ed660f134bf841708a7271f0b3b792ad48db..b75f9fb928fd03024d3349e1df663f6737592acb
 100644
--- a/lily/include/smobs.hh
+++ b/lily/include/smobs.hh
@@ -175,6 +175,15 @@ class Smob_base
   static Scm_init scm_init_;
   static void init (void);
   static std::string smob_name_;
+
+public:
+  void *operator new(size_t sz) {
+    return scm_gc_malloc(sz, "smob");
+  }
+  void operator delete(void *p) {
+    scm_gc_free(p, 0, "smob");
+  }
+
 protected:
   static Super *unchecked_unsmob (SCM s)
   {