I successfully cross compiled and built a static version of stunnel for ARM. It works with stunnel 5.70 and openssl 1.1.1b If however, I try to use openssl 1.1.1c, stunnel hangs. I narrowed the problem down to the following call in compression_init in ssl.c: comp_methods[COMP_NONE]=sk_SSL_COMP_new_null(); The program does not get past this point. I also tried to build with openssl 1.1.1v and 3.0.0, to no avail. I am using the following commands: To build openssl: ./Configure linux-armv4 --prefix=/home/erik/Documents/openssl-1.1.1b/install --openssldir=/home/erik/Documents/openssl-1.1.1b/install threads shared make CC=arm-linux-gnueabi-gcc make install To build stunnel: sed -i 's/^stunnel_LDFLAGS = /&-all-static /' src/Makefile.in export CFLAGS='-Os -fomit-frame-pointer -pipe' ./configure --with-ssl=/home/erik/Documents/openssl-1.1.1b/install --disable-fips --disable-shared --enable-static --disable-silent-rules --build x86_64-pc-linux-gnu --host arm-linux-gnueabi make What is the difference between openssl1.1.1b and 1.1.1c which causes this problem?