diff --git a/src/keymap_manager.hh b/src/keymap_manager.hh
index 64e39dd7..7474ed95 100644
--- a/src/keymap_manager.hh
+++ b/src/keymap_manager.hh
@@ -51,7 +51,7 @@ public:
             return m_parent->user_modes();
         return m_user_modes;
     }
-    void add_user_mode(const String user_mode_name);
+    void add_user_mode(String user_mode_name);
 
 private:
     KeymapManager()
diff --git a/src/shared_string.hh b/src/shared_string.hh
index a2c0345a..8455a31e 100644
--- a/src/shared_string.hh
+++ b/src/shared_string.hh
@@ -24,7 +24,7 @@ struct StringData : UseMemoryDomain<MemoryDomain::SharedString>
 private:
     StringData(int len) : refcount(0), length(len) {}
 
-    static constexpr uint32_t interned_flag = 1 << 31;
+    static constexpr uint32_t interned_flag = 1u << 31;
     static constexpr uint32_t refcount_mask = ~interned_flag;
 
     struct PtrPolicy
diff --git a/src/string_utils.cc b/src/string_utils.cc
index 212cab2e..459bea0b 100644
--- a/src/string_utils.cc
+++ b/src/string_utils.cc
@@ -21,7 +21,7 @@ String trim_indent(StringView str)
 
     utf8::iterator it{str.begin(), str};
     while (it != str.end() and is_horizontal_blank(*it))
-        it++;
+        ++it;
 
     const StringView indent{str.begin(), it.base()};
     return accumulate(str | split_after<StringView>('\n') | transform([&](auto&& line) {