The reproducer code below did not leak with MKL 11.3.1 but does with MKL 2018.3
Please ignore the (known) 2 leaks from dlopen that will be suppressed.
Tested on CentOS 7
#include <mkl.h>
int main(int argc, char* argv[])
{
mkl_thread_free_buffers();
mkl_free_buffers();
return 0;
}gcc -m64 -I${MKLROOT}/include -o mkl_test mkl_test.c -Wl,--start-group ${MKLROOT}/lib/intel64/libmkl_intel_lp64.a ${MKLROOT}/lib/intel64/libmkl_sequential.a ${MKLROOT}/lib/intel64/libmkl_core.a -Wl,--end-group -lpthread -lm -ldl
valgrind -v --tool=memcheck --track-origins=yes --leak-check=full --leak-resolution=high --show-reachable=yes ./mkl_test
==10454== Memcheck, a memory error detector
==10454== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==10454== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info
==10454== Command: ./mkl_test
==10454==
--10454-- Valgrind options:
--10454-- -v
--10454-- --tool=memcheck
--10454-- --track-origins=yes
--10454-- --leak-check=full
--10454-- --leak-resolution=high
--10454-- --show-reachable=yes
--10454-- Contents of /proc/version:
--10454-- Linux version 3.10.0-693.17.1.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-16) (GCC) ) #1 SMP Thu Jan 25 20:13:58 UTC 2018
--10454--
--10454-- Arch and hwcaps: AMD64, LittleEndian, amd64-cx16-lzcnt-rdtscp-sse3-avx-avx2-bmi
--10454-- Page sizes: currently 4096, max supported 4096
--10454-- Valgrind library directory: /usr/lib64/valgrind
--10454-- Reading syms from /home/user/mkl_test
--10454-- Reading syms from /usr/lib64/ld-2.17.so
--10454-- Considering /usr/lib/debug/usr/lib64/ld-2.17.so.debug ..
--10454-- .. CRC mismatch (computed 790ea11e wanted 61e7c7aa)
--10454-- Reading syms from /usr/lib64/valgrind/memcheck-amd64-linux
--10454-- object doesn't have a symbol table
--10454-- object doesn't have a dynamic symbol table
--10454-- Scheduler: using generic scheduler lock implementation.
--10454-- Reading suppressions file: /usr/lib64/valgrind/default.supp
==10454== embedded gdbserver: reading from /tmp/vgdb-pipe-from-vgdb-to-10454-by-user-on-centos7
==10454== embedded gdbserver: writing to /tmp/vgdb-pipe-to-vgdb-from-10454-by-user-on-centos7
==10454== embedded gdbserver: shared mem /tmp/vgdb-pipe-shared-mem-vgdb-10454-by-user-on-centos7
==10454==
==10454== TO CONTROL THIS PROCESS USING vgdb (which you probably
==10454== don't want to do, unless you know exactly what you're doing,
==10454== or are doing some strange experiment):
==10454== /usr/lib64/valgrind/../../bin/vgdb --pid=10454 ...command...
==10454==
==10454== TO DEBUG THIS PROCESS USING GDB: start GDB like this
==10454== /path/to/gdb ./mkl_test
==10454== and then give GDB the following command
==10454== target remote | /usr/lib64/valgrind/../../bin/vgdb --pid=10454
==10454== --pid is optional if only one valgrind process is running
==10454==
--10454-- REDIR: 0x40192f0 (ld-linux-x86-64.so.2:strlen) redirected to 0x38058d51 (???)
--10454-- REDIR: 0x40190c0 (ld-linux-x86-64.so.2:index) redirected to 0x38058d6b (???)
--10454-- Reading syms from /usr/lib64/valgrind/vgpreload_core-amd64-linux.so
--10454-- Reading syms from /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so
==10454== WARNING: new redirection conflicts with existing -- ignoring it
--10454-- old: 0x040192f0 (strlen ) R-> (0000.0) 0x38058d51 ???
--10454-- new: 0x040192f0 (strlen ) R-> (2007.0) 0x04c2ca90 strlen
--10454-- REDIR: 0x4019270 (ld-linux-x86-64.so.2:strcmp) redirected to 0x4c2dbe0 (strcmp)
--10454-- REDIR: 0x4019e60 (ld-linux-x86-64.so.2:mempcpy) redirected to 0x4c30c60 (mempcpy)
--10454-- Reading syms from /usr/lib64/libpthread-2.17.so
--10454-- Considering /usr/lib/debug/usr/lib64/libpthread-2.17.so.debug ..
--10454-- .. CRC mismatch (computed 3a2d64c4 wanted f10d0e71)
--10454-- Reading syms from /usr/lib64/libm-2.17.so
--10454-- Considering /usr/lib/debug/usr/lib64/libm-2.17.so.debug ..
--10454-- .. CRC mismatch (computed 891563a8 wanted 9154abae)
--10454-- Reading syms from /usr/lib64/libdl-2.17.so
--10454-- Considering /usr/lib/debug/usr/lib64/libdl-2.17.so.debug ..
--10454-- .. CRC mismatch (computed 0991f466 wanted 053c8f89)
--10454-- Reading syms from /usr/lib64/libc-2.17.so
--10454-- Considering /usr/lib/debug/usr/lib64/libc-2.17.so.debug ..
--10454-- .. CRC mismatch (computed 80a68b7f wanted 7faa757e)
--10454-- REDIR: 0x55e1f80 (libc.so.6:strcasecmp) redirected to 0x4a247b0 (_vgnU_ifunc_wrapper)
--10454-- REDIR: 0x55ded00 (libc.so.6:strnlen) redirected to 0x4a247b0 (_vgnU_ifunc_wrapper)
--10454-- REDIR: 0x55e4250 (libc.so.6:strncasecmp) redirected to 0x4a247b0 (_vgnU_ifunc_wrapper)
--10454-- REDIR: 0x55e1760 (libc.so.6:memset) redirected to 0x4a247b0 (_vgnU_ifunc_wrapper)
--10454-- REDIR: 0x55e1710 (libc.so.6:memcpy@GLIBC_2.2.5) redirected to 0x4a247b0 (_vgnU_ifunc_wrapper)
--10454-- REDIR: 0x55dec20 (libc.so.6:__GI_strlen) redirected to 0x4c2c9f0 (__GI_strlen)
--10454-- REDIR: 0x55e06f0 (libc.so.6:__GI_strrchr) redirected to 0x4c2c450 (__GI_strrchr)
--10454-- REDIR: 0x55e17c0 (libc.so.6:__GI_memset) redirected to 0x4c2fe80 (memset)
--10454-- REDIR: 0x55d8ab0 (libc.so.6:calloc) redirected to 0x4c2b8df (calloc)
--10454-- REDIR: 0x55d80c0 (libc.so.6:malloc) redirected to 0x4c29b5c (malloc)
--10454-- REDIR: 0x55d84c0 (libc.so.6:free) redirected to 0x4c2ac56 (free)
==10454==
==10454== HEAP SUMMARY:
==10454== in use at exit: 87 bytes in 3 blocks
==10454== total heap usage: 4 allocs, 1 frees, 134 bytes allocated
==10454==
==10454== Searching for pointers to 3 not-freed blocks
==10454== Checked 195,944 bytes
==10454==
==10454== 8 bytes in 1 blocks are still reachable in loss record 1 of 3
==10454== at 0x4C29BE3: malloc (vg_replace_malloc.c:299)
==10454== by 0x406FF1: mkl_serv_thread_free_buffers (in /home/user/mkl_test)
==10454== by 0x4010C0: main (in /home/user/mkl_test)
==10454==
==10454== 32 bytes in 1 blocks are still reachable in loss record 2 of 3
==10454== at 0x4C2B975: calloc (vg_replace_malloc.c:711)
==10454== by 0x535561F: _dlerror_run (in /usr/lib64/libdl-2.17.so)
==10454== by 0x5355050: dlopen@@GLIBC_2.2.5 (in /usr/lib64/libdl-2.17.so)
==10454== by 0x40D432: mkl_serv_inspector_suppress (in /home/user/mkl_test)
==10454== by 0x40D38C: mkl_serv_lock (in /home/user/mkl_test)
==10454== by 0x407032: mkl_serv_thread_free_buffers (in /home/user/mkl_test)
==10454== by 0x4010C0: main (in /home/user/mkl_test)
==10454==
==10454== 47 bytes in 1 blocks are still reachable in loss record 3 of 3
==10454== at 0x4C29BE3: malloc (vg_replace_malloc.c:299)
==10454== by 0x400F0D0: _dl_signal_error (in /usr/lib64/ld-2.17.so)
==10454== by 0x40133A1: _dl_open (in /usr/lib64/ld-2.17.so)
==10454== by 0x5354FBA: dlopen_doit (in /usr/lib64/libdl-2.17.so)
==10454== by 0x400F2D3: _dl_catch_error (in /usr/lib64/ld-2.17.so)
==10454== by 0x53555BC: _dlerror_run (in /usr/lib64/libdl-2.17.so)
==10454== by 0x5355050: dlopen@@GLIBC_2.2.5 (in /usr/lib64/libdl-2.17.so)
==10454== by 0x40D432: mkl_serv_inspector_suppress (in /home/user/mkl_test)
==10454== by 0x40D38C: mkl_serv_lock (in /home/user/mkl_test)
==10454== by 0x407032: mkl_serv_thread_free_buffers (in /home/user/mkl_test)
==10454== by 0x4010C0: main (in /home/user/mkl_test)
==10454==
==10454== LEAK SUMMARY:
==10454== definitely lost: 0 bytes in 0 blocks
==10454== indirectly lost: 0 bytes in 0 blocks
==10454== possibly lost: 0 bytes in 0 blocks
==10454== still reachable: 87 bytes in 3 blocks
==10454== suppressed: 0 bytes in 0 blocks
==10454==
==10454== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
==10454== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)