e.g.:
```
$ LD_LIBRARY_PATH=../src/.libs valgrind .libs/dwggrep -i tekst ../../test/test-data/example_r13.dwg
==1418971== Memcheck, a memory error detector
==1418971== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==1418971== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==1418971== Command: .libs/dwggrep -i tekst ../../test/test-data/example_r13.dwg
==1418971== 
==1418971== Invalid read of size 16
==1418971==    at 0x657ACD9: ???
==1418971==    by 0x6A9741F: ???
==1418971==  Address 0x6a9742f is 15 bytes inside a block of size 18 alloc'd
==1418971==    at 0x4848899: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==1418971==    by 0x48DDA5C: bit_read_TV (bits.c:1705)
==1418971==    by 0x4A71D90: dwg_decode_DICTIONARY_private (dwg.spec:3111)
==1418971==    by 0x4A713DD: dwg_decode_DICTIONARY (dwg.spec:3028)
==1418971==    by 0x4EB6A58: dwg_decode_add_object (decode.c:5341)
==1418971==    by 0x48ED654: decode_R13_R2000 (decode.c:799)
==1418971==    by 0x48E411F: dwg_decode (decode.c:225)
==1418971==    by 0x48CF18B: dwg_read_file (dwg.c:261)
==1418971==    by 0x11C3BA: main (dwggrep.c:2013)

==1418971== Invalid read of size 16
==1418971==    at 0x657ACD9: ???
==1418971==    by 0x6A9747F: ???
==1418971==  Address 0x6a9748f is 15 bytes inside a block of size 28 alloc'd
==1418971==    at 0x4848899: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==1418971==    by 0x48DDA5C: bit_read_TV (bits.c:1705)
==1418971==    by 0x4A71D90: dwg_decode_DICTIONARY_private (dwg.spec:3111)
==1418971==    by 0x4A713DD: dwg_decode_DICTIONARY (dwg.spec:3028)
==1418971==    by 0x4EB6A58: dwg_decode_add_object (decode.c:5341)
==1418971==    by 0x48ED654: decode_R13_R2000 (decode.c:799)
==1418971==    by 0x48E411F: dwg_decode (decode.c:225)
==1418971==    by 0x48CF18B: dwg_read_file (dwg.c:261)
==1418971==    by 0x11C3BA: main (dwggrep.c:2013)

```
but many more.
valgrind errors in decode
This is a GitHub Issue
repo:libredwg
owner:LibreDWG
Title : valgrind errors in decode
Issue date:

--- start body ---
e.g.:
```
$ LD_LIBRARY_PATH=../src/.libs valgrind .libs/dwggrep -i tekst ../../test/test-data/example_r13.dwg
==1418971== Memcheck, a memory error detector
==1418971== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==1418971== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==1418971== Command: .libs/dwggrep -i tekst ../../test/test-data/example_r13.dwg
==1418971== 
==1418971== Invalid read of size 16
==1418971==    at 0x657ACD9: ???
==1418971==    by 0x6A9741F: ???
==1418971==  Address 0x6a9742f is 15 bytes inside a block of size 18 alloc'd
==1418971==    at 0x4848899: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==1418971==    by 0x48DDA5C: bit_read_TV (bits.c:1705)
==1418971==    by 0x4A71D90: dwg_decode_DICTIONARY_private (dwg.spec:3111)
==1418971==    by 0x4A713DD: dwg_decode_DICTIONARY (dwg.spec:3028)
==1418971==    by 0x4EB6A58: dwg_decode_add_object (decode.c:5341)
==1418971==    by 0x48ED654: decode_R13_R2000 (decode.c:799)
==1418971==    by 0x48E411F: dwg_decode (decode.c:225)
==1418971==    by 0x48CF18B: dwg_read_file (dwg.c:261)
==1418971==    by 0x11C3BA: main (dwggrep.c:2013)

==1418971== Invalid read of size 16
==1418971==    at 0x657ACD9: ???
==1418971==    by 0x6A9747F: ???
==1418971==  Address 0x6a9748f is 15 bytes inside a block of size 28 alloc'd
==1418971==    at 0x4848899: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==1418971==    by 0x48DDA5C: bit_read_TV (bits.c:1705)
==1418971==    by 0x4A71D90: dwg_decode_DICTIONARY_private (dwg.spec:3111)
==1418971==    by 0x4A713DD: dwg_decode_DICTIONARY (dwg.spec:3028)
==1418971==    by 0x4EB6A58: dwg_decode_add_object (decode.c:5341)
==1418971==    by 0x48ED654: decode_R13_R2000 (decode.c:799)
==1418971==    by 0x48E411F: dwg_decode (decode.c:225)
==1418971==    by 0x48CF18B: dwg_read_file (dwg.c:261)
==1418971==    by 0x11C3BA: main (dwggrep.c:2013)

```
but many more.
--- end body ---
