The following invocation of emacs aborts with double-free: $ installed/bin/emacs -Q -L . -batch --eval '(progn (message "before") (make-local-variable (make-symbol "\ s")) (kill-buffer) (garbage-collect) (garbage-collect) (message "after"))' before *** Error in `installed/bin/emacs': double free or corruption (!prev): 0x00000000014bff10 *** ======= Backtrace: ========= /lib64/libc.so.6(+0x7c619)[0x7efd02c32619] installed/bin/emacs[0x4e3fa1] installed/bin/emacs[0x4e917a] installed/bin/emacs[0x5006bc] installed/bin/emacs[0x500780] installed/bin/emacs[0x500439] installed/bin/emacs[0x503d30] installed/bin/emacs[0x500de6] installed/bin/emacs[0x538e31] installed/bin/emacs[0x500d63] installed/bin/emacs[0x538e31] installed/bin/emacs[0x500d63] installed/bin/emacs[0x538e31] installed/bin/emacs[0x4ffe73] installed/bin/emacs[0x5001a7] installed/bin/emacs[0x503d30] installed/bin/emacs[0x4ff454] installed/bin/emacs[0x49093c] installed/bin/emacs[0x4ff404] installed/bin/emacs[0x48e446] installed/bin/emacs[0x4928fe] installed/bin/emacs[0x492c15] installed/bin/emacs[0x406df3] /lib64/libc.so.6(__libc_start_main+0xf5)[0x7efd02bd7c05] installed/bin/emacs[0x4079de] In emacs-26, running this in gdb prevents the error so I don't have a backtrace (though I have seen such a backtrace on a different machine with different build options for emacs). In emacs 25.2, though, the same error happens and there the backtrace is: (gdb) bt full #0 0x00007ffff20a11f7 in raise () from /lib64/libc.so.6 No symbol table info available. #1 0x00007ffff20a28e8 in abort () from /lib64/libc.so.6 No symbol table info available. #2 0x00007ffff20e0f47 in __libc_message () from /lib64/libc.so.6 No symbol table info available. #3 0x00007ffff20e8619 in _int_free () from /lib64/libc.so.6 No symbol table info available. #4 0x00000000005358d1 in sweep_symbols () at alloc.c:6839 this_free = sym = 0xd667b0 end = 0xd667e0 sblk = 0xd66720 sprev = lim = num_free = num_used = 1087 #5 0x000000000053b76a in gc_sweep () at alloc.c:6982 No locals. #6 garbage_collect_1 (end=) at alloc.c:5799 nextb = stack_top_variable = 0 '\000' i = message_p = false count = start = {tv_sec = 1509372540, tv_nsec = 974388982} retval = 0 tot_before = 0 total = {12342819, 12341875, 12341619, 12341299, 12340147, 12340035, 12339907, 12339715, 12339571, 12337939, 12337091} #7 0x000000000053c0d9 in Fgarbage_collect () at alloc.c:5983 end = 0x7fffffffd348 #8 0x0000000000551c2b in eval_sub (form=) at eval.c:2169 i = maxargs = 0 args_left = 0 numargs = fun = 11669013 val = original_fun = original_args = 0 funcar = count = 13 argvals = {0, 0, 12067264, 0, 14009168, 176093659181, 0, 40} #9 0x0000000000551ead in Fprogn (body=16724163) at eval.c:431 val = #10 0x0000000000551b11 in eval_sub (form=) at eval.c:2125 args_left = 16725811 numargs = fun = 11695045 val = original_fun = 37680 original_args = 16725811 funcar = count = 12 argvals = {0, 0, 12274656, 4611686019484352512, 1, 4599230, 20285716, 5508133} #11 0x0000000000553712 in Feval (form=16725891, lexical=) at eval.c:1994 count = 11 #12 0x0000000000552648 in Ffuncall (nargs=, args=0x7fffffffd588) at eval.c:2702 internal_argbuf = {16725891, 0, 0, 4599230, 9895560, 5508133, 22, 9893584} fun = 11696197 original_fun = funcar = numargs = lisp_numargs = 6 val = internal_args = 0x7fffffffd590 count = 10 #13 0x000000000058941d in exec_byte_code (bytestr=, vector=9893581, maxdepth=, args_template=, nargs=, args=) at bytecode.c:880 targets = {0x5894ba , 0x58b452 , 0x58b457 , 0x58b45c , 0x589282 , 0x589288 , 0x58952e , 0x5895ad , 0x5895a3 , 0x5895a8 , 0x589573 , 0x589578 , 0x5892c1 , 0x5892c8 , 0x5896e9 , 0x58957d , 0x589908 , 0x58990d , 0x589879 , 0x58987e , 0x589334 , 0x589338 , 0x589820 , 0x5897fa , 0x5896ae , 0x5896b3 , 0x5896b8 , 0x5896c5 , 0x5893b4 , 0x5893b8 , 0x589865 , 0x589688 , 0x589679 , 0x58967e , 0x589683 , 0x58964e , 0x5893f9 , 0x589400 , 0x5896d5 , 0x589653 , 0x58a53f , ---Type to continue, or q to quit--- 0x58a544 , 0x58a549 , 0x58a514 , 0x589443 , 0x589448 , 0x58a4d6 , 0x58a519 , 0x58a944 , 0x58a77d , 0x58a70b , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x589d04 , 0x589d90 , 0x589dc7 , 0x589e01 , 0x589e3b , 0x5897bb , 0x589883 , 0x589e81 , 0x589773 , 0x5898c0 , 0x589eb3 , 0x589ef0 , 0x589f22 , 0x589f5f , 0x589f98 , 0x58a022 , 0x58a054 , 0x58a091 , 0x58a0dc , 0x58a10e , 0x58a140 , 0x58a17d , 0x58a1ba , 0x58a1f7 , 0x58a23e , 0x58a277 , 0x58a2b0 , 0x58a33d , 0x58a380 , 0x58a3c7 , 0x58a494 , 0x58a410 , 0x58a452 , 0x589bb4 , 0x589bf6 , 0x589c2f , 0x589c71 , 0x58b195 , 0x58b1ce , 0x58b207 , 0x58afea , 0x589489 , 0x58b02b , 0x58b059 , 0x58b0e1 , 0x58b122 , 0x58b163 , 0x58ac6d , 0x58ac9d , 0x58accd , 0x58ad05 , 0x5894ba , 0x58ad39 , 0x58ad69 , 0x58ad99 , 0x58adc9 , 0x58adf9 , 0x58ae29 , 0x589489 , 0x5894ba , 0x58ae5b , 0x58ae9d , 0x58aecf , 0x58af01 , 0x58af3e , 0x58af7b , 0x58ac0e , 0x58ac30 , 0x58b63e , 0x58b67b , 0x58b60e , 0x58b735 , 0x5894ba , 0x58aada , 0x58a555 , 0x5896fd , 0x58a5e4 , 0x58a825 , 0x58a896 , 0x589b72 , 0x58a801 , 0x589834 , 0x5894fd , 0x589912 , 0x58a698 , 0x58a6c9 , 0x58abbf , 0x58ab2d , 0x58ab74 , 0x589caa , 0x58a4ea , 0x58b6b8 , 0x58b703 , 0x58b465 , 0x58b497 , 0x58b4c9 , 0x58b4fb , 0x58b538 , 0x58b575 , 0x58b5b2 , 0x58b5ef , 0x58b279 , 0x58b2b6 , 0x58b2f3 , 0x58b325 , 0x58b362 , 0x58b39f , 0x58b3dc , 0x58b419 , 0x58b240 , 0x58afad , 0x589975 , 0x5899be , 0x5894ba , 0x58a784 , 0x58aa0f , 0x58a975 , 0x58aa76 , 0x589adc , 0x589fd1 , 0x58a2e9 , 0x58b08d , 0x589606 , 0x5899f8 , 0x5894ba , 0x5894ba , 0x589a54 , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x589aa2 } count = 8 op = 1 vectorp = 0x96f6d0 stack = { pc = 0xaaa4a8 "\210\202L\003\016A权\317\001\313\347\350\016C\"\003\206m\001\n\211A\022\242\211\262\r\313\332\036D\322\003\003\003#)\266\203\203\211\001\006\n\327\313O\262\vڲ\001\351\352\006\f!!\262\v\211\203\252\001\314\016E\006\fC\"\026E\006\t\203\313\001\016E\262\n\202\313\001\006\t\203\301\001\006\t\006\v\006\vAB\241\210\006\tA\262\n\202\313\001\006\n\016EB\211\026E\262\n\210\202L\003\016A띃\367\001\352\002\206\340\001\n\211A\022\242!\351\001!\354\001!\203\355\001\211\262\002\355\002\313\332#\266\003\202L\003\016A\027\002\352\002\206\b\002\n\211A\022\242!\351\001!\355\001\313ډ$\266\003\202L\003\016", ..., byte_string = 9893548, byte_string_start = 0xaaa355 "\306 \210\b\203\021", next = 0x7fffffffd900} top = 0x7fffffffd680 result = type = #14 0x00000000005523c3 in Ffuncall (nargs=, args=0x7fffffffd818) at eval.c:2760 fun = original_fun = 8587296 funcar = numargs = lisp_numargs = 6 val = internal_args = count = 7 #15 0x000000000058941d in exec_byte_code (bytestr=, vector=9870557, maxdepth=, args_template=, nargs=, args=) at bytecode.c:880 targets = {0x5894ba , 0x58b452 , 0x58b457 , 0x58b45c , 0x589282 , 0x589288 , 0x58952e , 0x5895ad , 0x5895a3 , 0x5895a8 , 0x589573 , 0x589578 , 0x5892c1 , 0x5892c8 , 0x5896e9 , 0x58957d , 0x589908 , 0x58990d , 0x589879 , 0x58987e , ---Type to continue, or q to quit--- 0x589334 , 0x589338 , 0x589820 , 0x5897fa , 0x5896ae , 0x5896b3 , 0x5896b8 , 0x5896c5 , 0x5893b4 , 0x5893b8 , 0x589865 , 0x589688 , 0x589679 , 0x58967e , 0x589683 , 0x58964e , 0x5893f9 , 0x589400 , 0x5896d5 , 0x589653 , 0x58a53f , 0x58a544 , 0x58a549 , 0x58a514 , 0x589443 , 0x589448 , 0x58a4d6 , 0x58a519 , 0x58a944 , 0x58a77d , 0x58a70b , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x5894ba , 0x589d04 , 0x589d90 , 0x589dc7 , 0x589e01 , 0x589e3b , 0x5897bb , 0x589883 , 0x589e81 , 0x589773 , 0x5898c0 , 0x589eb3 , 0x589ef0 , 0x589f22 , 0x589f5f , 0x589f98 , 0x58a022 , 0x58a054 , 0x58a091 , 0x58a0dc , 0x58a10e , 0x58a140 , 0x58a17d , 0x58a1ba , 0x58a1f7 , 0x58a23e , 0x58a277 , 0x58a2b0 , 0x58a33d , 0x58a380 , 0x58a3c7 , 0x58a494 , 0x58a410 , 0x58a452 , 0x589bb4 , 0x589bf6 , 0x589c2f , 0x589c71 , 0x58b195 , 0x58b1ce , 0x58b207 , 0x58afea , 0x589489 , 0x58b02b , 0x58b059 , 0x58b0e1 , 0x58b122 , 0x58b163 , 0x58ac6d , 0x58ac9d , 0x58accd , 0x58ad05 , 0x5894ba , 0x58ad39 , 0x58ad69 , 0x58ad99 , 0x58adc9 , 0x58adf9 , 0x58ae29 , 0x589489 , 0x5894ba , 0x58ae5b , 0x58ae9d , 0x58aecf , 0x58af01 , 0x58af3e , 0x58af7b , 0x58ac0e , 0x58ac30 , 0x58b63e , 0x58b67b , 0x58b60e , 0x58b735 , 0x5894ba , 0x58aada , 0x58a555 , 0x5896fd , 0x58a5e4 , 0x58a825 , 0x58a896 , 0x589b72 , 0x58a801 , 0x589834 , 0x5894fd , 0x589912 , 0x58a698 , 0x58a6c9 , 0x58abbf , 0x58ab2d , 0x58ab74 , 0x589caa , 0x58a4ea , 0x58b6b8 , 0x58b703 , 0x58b465 , 0x58b497 , 0x58b4c9 , 0x58b4fb , 0x58b538 , 0x58b575 , 0x58b5b2