Libgcrypt 1.8.0 reveals an error on FreeBSD 12-CURRENT using LLVM 5.0.0 (no LLVM LLD used!):
[...] libtool: compile: cc -DHAVE_CONFIG_H -I. -I.. -I../src -I../src -I/usr/local/include -O0 -pipe -O3 -fstack-protector -fno-strict-aliasing -std=gnu89 -fvisibility=hidden -Wall -c ./rndjent.c -fPIC -DPIC -o .libs/rndjent.o In file included from ./rndjent.c:86: ./jitterentropy-base.c:53:13: warning: unknown pragma ignored [-Wunknown-pragmas] #pragma GCC optimize ("O0") ^ ./jitterentropy-base.c:60:4: error: "The CPU Jitter random number generator must not be compiled with optimizations. See documentation. Use the compiler switch -O0 for compiling jitterentropy-base.c." #error "The CPU Jitter random number generator must not be compiled with optimizations. See documentation. Use the compiler switch -O0 for compiling jitterentropy-base.c." ^ 1 warning and 1 error generated. *** [rndjent.lo] Error code 1 make[4]: stopped in /usr/ports/security/libgcrypt/work/libgcrypt-1.8.0/random --- random-system.lo ---