Heap exhausted after method redefinition and ignored related errors

[Siebe de Vos]

Running the code in the attachment generates errors in PCL code (<bug to be reported>), which are then ignored. It runs out of heap after some time. Running the same with gc-logfile shows that GC is happening, but allocation increases.

sbcl --dynamic-space-size 160 --load method-heap-exhaust.lisp
This is SBCL 1.4.5, an implementation of ANSI Common Lisp.
[...]
Heap exhausted during garbage collection: 16 bytes available, 32 requested.
Gen Boxed Unboxed LgBox LgUnbox Pin Alloc Waste Trig WP GCs Mem-age
 0 0 0 0 0 0 0 0 1677721 0 0 0.0000
 1 0 0 0 0 0 0 0 1677721 0 0 0.0000
 2 0 0 0 0 0 0 0 1677721 0 0 0.0000
 3 0 0 0 0 0 0 0 1677721 0 0 0.0000
 4 1309 1 0 0 17 42518080 408000 1677721 0 0 1.2049
 5 1835 2 65 66 31 64043168 444256 2000000 1866 0 0.0000
 6 524 267 0 0 0 25083184 836304 2000000 499 0 0.0000
 7 792 0 129 130 0 34331632 107536 2000000 0 0 0.0000
           Total bytes allocated = 165976064
           Dynamic-space-size bytes = 167772160
GC control variables:
   *GC-INHIBIT* = true
   *GC-PENDING* = true
   *STOP-FOR-GC-PENDING* = false
fatal error encountered in SBCL pid 8277(tid 0x7ffff7fc9740):
Heap exhausted, game over.

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Linux si2l 4.4.92-31-default #1 SMP Sun Oct 22 06:56:24 UTC 2017 (1d80e8a) x86_64 x86_64 x86_64 GNU/Linux

*features* =>
(:64-BIT :64-BIT-REGISTERS :ALIEN-CALLBACKS :ANSI-CL :ASH-RIGHT-VOPS
 :C-STACK-IS-CONTROL-STACK :CALL-SYMBOL :COMMON-LISP :COMPACT-INSTANCE-HEADER
 :COMPARE-AND-SWAP-VOPS :COMPLEX-FLOAT-VOPS :CYCLE-COUNTER :ELF :FLOAT-EQL-VOPS
 :FP-AND-PC-STANDARD-SAVE :GCC-TLS :GENCGC :IEEE-FLOATING-POINT :IMMOBILE-CODE
 :IMMOBILE-SPACE :INLINE-CONSTANTS :INTEGER-EQL-VOP :LARGEFILE :LINKAGE-TABLE
 :LINUX :LITTLE-ENDIAN :MEMORY-BARRIER-VOPS :MULTIPLY-HIGH-VOPS
 :OS-PROVIDES-BLKSIZE-T :OS-PROVIDES-DLADDR :OS-PROVIDES-DLOPEN
 :OS-PROVIDES-GETPROTOBY-R :OS-PROVIDES-POLL :OS-PROVIDES-PUTWC
 :OS-PROVIDES-SUSECONDS-T :PACKAGE-LOCAL-NICKNAMES :RAW-INSTANCE-INIT-VOPS
 :RAW-SIGNED-WORD :RELOCATABLE-HEAP :SB-DOC :SB-EVAL :SB-FUTEX :SB-LDB
 :SB-PACKAGE-LOCKS :SB-SIMD-PACK :SB-SOURCE-LOCATIONS :SB-THREAD :SB-UNICODE
 :SBCL :STACK-ALLOCATABLE-CLOSURES :STACK-ALLOCATABLE-FIXED-OBJECTS
 :STACK-ALLOCATABLE-LISTS :STACK-ALLOCATABLE-VECTORS
 :STACK-GROWS-DOWNWARD-NOT-UPWARD :SYMBOL-INFO-VOPS :UNBIND-N-VOP
 :UNDEFINED-FUN-RESTARTS :UNIX :UNWIND-TO-FRAME-AND-CALL-VOP :X86-64)

[Siebe de Vos (s.de.vos)]

The bug is not reproducible today.

The fix appears to be this commit:
commit 6c7536b0ac79d78868a0b24c71dd7f1dd7f47765
Author: Douglas Katzman <email address hidden>
Date: Thu Jun 11 23:30:01 2020 -0400

    Change *effective-method-cache* into a per-method slot

 src/pcl/boot.lisp | 9 ++++++++-
 src/pcl/defs.lisp | 1 +
 src/pcl/dfun.lisp | 36 +++++++++++++++---------------------
 3 files changed, 24 insertions(+), 22 deletions(-)

which corresponds to SBCL 2.0.5.57-6c7536b0a .