Index: src/tls.c
--- src/tls.c.orig
+++ src/tls.c
@@ -41,7 +41,7 @@
 volatile int tls_initialized=0;
 
 NOEXPORT void tls_platform_init();
-#if OPENSSL_VERSION_NUMBER<0x10100000L
+#if OPENSSL_VERSION_NUMBER<0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 NOEXPORT void free_function(void *);
 #endif
 
@@ -52,7 +52,7 @@ void tls_init() {
     tls_platform_init();
     tls_initialized=1;
     ui_tls=tls_alloc(NULL, NULL, "ui");
-#if OPENSSL_VERSION_NUMBER>=0x10100000L
+#if OPENSSL_VERSION_NUMBER>=0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)
     CRYPTO_set_mem_functions(str_alloc_detached_debug,
         str_realloc_detached_debug, str_free_debug);
 #else
@@ -184,7 +184,7 @@ TLS_DATA *tls_get() {
 
 /**************************************** OpenSSL allocator hook */
 
-#if OPENSSL_VERSION_NUMBER<0x10100000L
+#if OPENSSL_VERSION_NUMBER<0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 NOEXPORT void free_function(void *ptr) {
     /* CRYPTO_set_mem_ex_functions() needs a function rather than a macro */
     /* unfortunately, OpenSSL provides no file:line information here */