diff --git a/src/dwarfs/terminal.cpp b/src/dwarfs/terminal.cpp
index 8dd6e5ac..bdb8eeb1 100644
--- a/src/dwarfs/terminal.cpp
+++ b/src/dwarfs/terminal.cpp
@@ -40,7 +40,7 @@ bool stream_is_fancy_terminal(std::ostream& os) {
     return false;
   }
   auto term = ::getenv("TERM");
-  return term && term[0] && ::strcmp(term, "dumb");
+  return term && term[0] != '\0' && ::strcmp(term, "dumb") != 0;
 }
 
 char const* terminal_color(termcolor color) {
diff --git a/src/dwarfs/util.cpp b/src/dwarfs/util.cpp
index 44f7fe2e..95451b16 100644
--- a/src/dwarfs/util.cpp
+++ b/src/dwarfs/util.cpp
@@ -63,15 +63,15 @@ size_t parse_size_with_unit(const std::string& str) {
     case 't':
     case 'T':
       size <<= 10;
-      // fallthrough
+      [[fallthrough]];
     case 'g':
     case 'G':
       size <<= 10;
-      // fallthrough
+      [[fallthrough]];
     case 'm':
     case 'M':
       size <<= 10;
-      // fallthrough
+      [[fallthrough]];
     case 'k':
     case 'K':
       size <<= 10;
diff --git a/src/dwarfs/worker_group.cpp b/src/dwarfs/worker_group.cpp
index f8d71e2e..fce69e30 100644
--- a/src/dwarfs/worker_group.cpp
+++ b/src/dwarfs/worker_group.cpp
@@ -239,7 +239,7 @@ class load_adaptive_policy {
 
   load_adaptive_policy(size_t workers)
       : sem_(workers)
-      , max_throttled_(workers - 1) {}
+      , max_throttled_(static_cast<int>(workers) - 1) {}
 
   void start_task() { sem_.acquire(); }