diff --git a/scripts/mk_util.py b/scripts/mk_util.py
index 3ca0012e7..53f891d28 100644
--- a/scripts/mk_util.py
+++ b/scripts/mk_util.py
@@ -596,7 +596,7 @@ def display_help(exit_code):
     else:
         print("  --parallel=num                use cl option /MP with 'num' parallel processes")
     print("  --pypkgdir=<dir>              Force a particular Python package directory (default %s)" % PYTHON_PACKAGE_DIR)
-    print("  -b <sudir>, --build=<subdir>  subdirectory where Z3 will be built (default: build).")
+    print("  -b <subdir>, --build=<subdir>  subdirectory where Z3 will be built (default: %s)." % BUILD_DIR)
     print("  --githash=hash                include the given hash in the binaries.")
     print("  -d, --debug                   compile Z3 in debug mode.")
     print("  -t, --trace                   enable tracing in release mode.")
@@ -742,7 +742,8 @@ def extract_c_includes(fname):
 
 # Given a path dir1/subdir2/subdir3 returns ../../..
 def reverse_path(p):
-    l = p.split(os.sep)
+    # Filter out empty components (e.g. will have one if path ends in a slash)
+    l = list(filter(lambda x: len(x) > 0, p.split(os.sep)))
     n = len(l)
     r = '..'
     for i in range(1, n):
diff --git a/src/util/debug.cpp b/src/util/debug.cpp
index 54c67feca..66676c619 100644
--- a/src/util/debug.cpp
+++ b/src/util/debug.cpp
@@ -76,7 +76,7 @@ void invoke_gdb() {
     for (;;) {
         std::cerr << "(C)ontinue, (A)bort, (S)top, (T)hrow exception, Invoke (G)DB\n";
         char result;
-        bool ok = (std::cin >> result);
+        bool ok = bool(std::cin >> result);
         if (!ok) exit(ERR_INTERNAL_FATAL); // happens if std::cin is eof or unattached.
         switch(result) {
         case 'C':