diff --git a/Makefile b/Makefile
index 25290b81..192d3d78 100644
--- a/Makefile
+++ b/Makefile
@@ -67,7 +67,7 @@ include/GENERATED_tokens.h: include/GENERATED_call.h
 # and once as an object file for i3.
 src/commands_parser.o: src/commands_parser.c ${HEADERS} ${CMDPARSE_HEADERS}
 	echo "[i3] CC $<"
-	$(CC) $(CPPFLAGS) $(CFLAGS) -DTEST_PARSER -DLOGLEVEL="((uint64_t)1 << $(shell awk '/$(shell basename $< .c)/ { print NR; exit 0; }' loglevels.tmp))" -o test.commands_parser $< $(LIBS)
+	$(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) -DTEST_PARSER -DLOGLEVEL="((uint64_t)1 << $(shell awk '/$(shell basename $< .c)/ { print NR; exit 0; }' loglevels.tmp))" -o test.commands_parser $< $(LIBS)
 	$(CC) $(CPPFLAGS) $(CFLAGS) -DLOGLEVEL="((uint64_t)1 << $(shell awk '/$(shell basename $< .c)/ { print NR; exit 0; }' loglevels.tmp))" -c -o $@ $<
 
 src/cfgparse.yy.o: src/cfgparse.l src/cfgparse.y.o ${HEADERS}
diff --git a/common.mk b/common.mk
index 537d4dda..43949059 100644
--- a/common.mk
+++ b/common.mk
@@ -68,7 +68,10 @@ CPPFLAGS += -DPCRE_HAS_UCP=1
 endif
 
 LIBS += -lm
+# Darwin (Mac OS X) doesn’t have librt
+ifneq ($(UNAME),Darwin)
 LIBS += -lrt
+endif
 LIBS += -L $(TOPDIR)/libi3 -li3
 LIBS += $(call ldflags_for_lib, xcb-event,xcb-event)
 LIBS += $(call ldflags_for_lib, xcb-keysyms,xcb-keysyms)
diff --git a/src/log.c b/src/log.c
index fd98081b..92e8f57c 100644
--- a/src/log.c
+++ b/src/log.c
@@ -18,6 +18,10 @@
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <errno.h>
+#if defined(__APPLE__)
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#endif
 
 #include "util.h"
 #include "log.h"
@@ -93,8 +97,15 @@ void init_logging(void) {
          * For 512 MiB of RAM this will lead to a 5 MiB log buffer.
          * At the moment (2011-12-10), no testcase leads to an i3 log
          * of more than ~ 600 KiB. */
-        long long physical_mem_bytes = (long long)sysconf(_SC_PHYS_PAGES) *
-                                                  sysconf(_SC_PAGESIZE);
+        long long physical_mem_bytes;
+#if defined(__APPLE__)
+        int mib[2] = { CTL_HW, HW_MEMSIZE };
+        size_t length = sizeof(long long);
+        sysctl(mib, 2, &physical_mem_bytes, &length, NULL, 0);
+#else
+        physical_mem_bytes = (long long)sysconf(_SC_PHYS_PAGES) *
+                                        sysconf(_SC_PAGESIZE);
+#endif
         logbuffer_size = min(physical_mem_bytes * 0.01, shmlog_size);
         sasprintf(&shmlogname, "/i3-log-%d", getpid());
         logbuffer_shm = shm_open(shmlogname, O_RDWR | O_CREAT | O_TRUNC, S_IREAD | S_IWRITE);
@@ -199,11 +210,6 @@ static void vlog(const bool print, const char *fmt, va_list args) {
         vprintf(fmt, args);
     } else {
         len += vsnprintf(message + len, sizeof(message) - len, fmt, args);
-        if (len < 0 ) {
-            fprintf(stderr, "BUG: something is overflowing here. Dropping the log entry\n");
-            return;
-        }
-
         if (len >= sizeof(message)) {
             fprintf(stderr, "BUG: single log message > 4k\n");
         }