diff --git a/src/nvim/cmdhist.c b/src/nvim/cmdhist.c
index 81b93e5304..23256694af 100644
--- a/src/nvim/cmdhist.c
+++ b/src/nvim/cmdhist.c
@@ -204,7 +204,7 @@ static inline void clear_hist_entry(histentry_T *hisptr)
 /// If 'move_to_front' is true, matching entry is moved to end of history.
 ///
 /// @param move_to_front  Move the entry to the front if it exists
-static int in_history(int type, char *str, int move_to_front, int sep)
+static int in_history(int type, const char *str, int move_to_front, int sep)
 {
   int last_i = -1;
 
@@ -238,7 +238,7 @@ static int in_history(int type, char *str, int move_to_front, int sep)
   }
 
   list_T *const list = history[type][i].additional_elements;
-  str = history[type][i].hisstr;
+  char *const save_hisstr = history[type][i].hisstr;
   while (i != hisidx[type]) {
     if (++i >= hislen) {
       i = 0;
@@ -248,7 +248,7 @@ static int in_history(int type, char *str, int move_to_front, int sep)
   }
   tv_list_unref(list);
   history[type][i].hisnum = ++hisnum[type];
-  history[type][i].hisstr = str;
+  history[type][i].hisstr = save_hisstr;
   history[type][i].timestamp = os_time();
   history[type][i].additional_elements = NULL;
   return true;
@@ -295,7 +295,7 @@ static int last_maptick = -1;           // last seen maptick
 /// @param histype  may be one of the HIST_ values.
 /// @param in_map   consider maptick when inside a mapping
 /// @param sep      separator character used (search hist)
-void add_to_history(int histype, char *new_entry, int in_map, int sep)
+void add_to_history(int histype, const char *new_entry, int in_map, int sep)
 {
   histentry_T *hisptr;
 
@@ -538,7 +538,7 @@ void f_histadd(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
 
   init_history();
-  add_to_history(histype, (char *)str, false, NUL);
+  add_to_history(histype, str, false, NUL);
   rettv->vval.v_number = true;
 }
 
diff --git a/src/nvim/eval/funcs.c b/src/nvim/eval/funcs.c
index c56b8da896..3f6a876838 100644
--- a/src/nvim/eval/funcs.c
+++ b/src/nvim/eval/funcs.c
@@ -925,8 +925,7 @@ static void f_confirm(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
 
   if (!error) {
-    rettv->vval.v_number = do_dialog(type, NULL, (char *)message, (char *)buttons, def, NULL,
-                                     false);
+    rettv->vval.v_number = do_dialog(type, NULL, message, buttons, def, NULL, false);
   }
 }
 
diff --git a/src/nvim/ex_cmds.c b/src/nvim/ex_cmds.c
index d061345453..b43a509ca2 100644
--- a/src/nvim/ex_cmds.c
+++ b/src/nvim/ex_cmds.c
@@ -388,7 +388,7 @@ typedef struct {
 static int string_compare(const void *s1, const void *s2) FUNC_ATTR_NONNULL_ALL
 {
   if (sort_lc) {
-    return strcoll((char *)s1, (char *)s2);
+    return strcoll((const char *)s1, (const char *)s2);
   }
   return sort_ic ? STRICMP(s1, s2) : strcmp(s1, s2);
 }
diff --git a/src/nvim/message.c b/src/nvim/message.c
index 55a455a7c2..1f5d1d0e60 100644
--- a/src/nvim/message.c
+++ b/src/nvim/message.c
@@ -3503,8 +3503,8 @@ void msg_advance(int col)
 /// @param textfiel  IObuff for inputdialog(), NULL otherwise
 /// @param ex_cmd  when true pressing : accepts default and starts Ex command
 /// @returns 0 if cancelled, otherwise the nth button (1-indexed).
-int do_dialog(int type, char *title, char *message, char *buttons, int dfltbutton, char *textfield,
-              int ex_cmd)
+int do_dialog(int type, const char *title, const char *message, const char *buttons, int dfltbutton,
+              const char *textfield, int ex_cmd)
 {
   int retval = 0;
   char *hotkeys;
@@ -3611,7 +3611,7 @@ static int copy_char(const char *from, char *to, bool lowercase)
 ///                        corresponding button has a hotkey
 ///
 /// @return Pointer to memory allocated for storing hotkeys
-static char *console_dialog_alloc(const char *message, char *buttons, bool has_hotkey[])
+static char *console_dialog_alloc(const char *message, const char *buttons, bool has_hotkey[])
 {
   int lenhotkey = HOTK_LEN;  // count first button
   has_hotkey[0] = false;
@@ -3619,7 +3619,7 @@ static char *console_dialog_alloc(const char *message, char *buttons, bool has_h
   // Compute the size of memory to allocate.
   int len = 0;
   int idx = 0;
-  char *r = buttons;
+  const char *r = buttons;
   while (*r) {
     if (*r == DLG_BUTTON_SEP) {
       len += 3;                         // '\n' -> ', '; 'x' -> '(x)'
@@ -3665,7 +3665,7 @@ static char *console_dialog_alloc(const char *message, char *buttons, bool has_h
 /// The hotkeys can be multi-byte characters, but without combining chars.
 ///
 /// @return  an allocated string with hotkeys.
-static char *msg_show_console_dialog(char *message, char *buttons, int dfltbutton)
+static char *msg_show_console_dialog(const char *message, const char *buttons, int dfltbutton)
   FUNC_ATTR_NONNULL_RET
 {
   bool has_hotkey[HAS_HOTKEY_LEN] = { false };
@@ -3685,7 +3685,7 @@ static char *msg_show_console_dialog(char *message, char *buttons, int dfltbutto
 /// @param has_hotkey An element in this array is true if corresponding button
 ///                   has a hotkey
 /// @param[out] hotkeys_ptr Pointer to the memory location where hotkeys will be copied
-static void copy_hotkeys_and_msg(const char *message, char *buttons, int default_button_idx,
+static void copy_hotkeys_and_msg(const char *message, const char *buttons, int default_button_idx,
                                  const bool has_hotkey[], char *hotkeys_ptr)
 {
   *confirm_msg = '\n';
@@ -3708,7 +3708,7 @@ static void copy_hotkeys_and_msg(const char *message, char *buttons, int default
   }
 
   int idx = 0;
-  char *r = buttons;
+  const char *r = buttons;
   while (*r) {
     if (*r == DLG_BUTTON_SEP) {
       *msgp++ = ',';
diff --git a/src/nvim/path.c b/src/nvim/path.c
index 9239668717..c0d1eff49e 100644
--- a/src/nvim/path.c
+++ b/src/nvim/path.c
@@ -1805,7 +1805,7 @@ bool path_with_extension(const char *path, const char *extension)
 }
 
 /// Return true if "name" is a full (absolute) path name or URL.
-bool vim_isAbsName(char *name)
+bool vim_isAbsName(const char *name)
 {
   return path_with_url(name) != 0 || path_is_absolute(name);
 }
@@ -1866,7 +1866,7 @@ char *fix_fname(const char *fname)
 #ifdef UNIX
   return FullName_save(fname, true);
 #else
-  if (!vim_isAbsName((char *)fname)
+  if (!vim_isAbsName(fname)
       || strstr(fname, "..") != NULL
       || strstr(fname, "//") != NULL
 # ifdef BACKSLASH_IN_FILENAME
diff --git a/src/nvim/statusline.c b/src/nvim/statusline.c
index 3989b91203..2a60ec2bb2 100644
--- a/src/nvim/statusline.c
+++ b/src/nvim/statusline.c
@@ -248,8 +248,8 @@ StlClickDefinition *stl_alloc_click_defs(StlClickDefinition *cdp, long width, si
 }
 
 /// Fill the click definitions array if needed.
-void stl_fill_click_defs(StlClickDefinition *click_defs, StlClickRecord *click_recs, char *buf,
-                         int width, bool tabline)
+void stl_fill_click_defs(StlClickDefinition *click_defs, StlClickRecord *click_recs,
+                         const char *buf, int width, bool tabline)
 {
   if (click_defs == NULL) {
     return;
@@ -270,7 +270,7 @@ void stl_fill_click_defs(StlClickDefinition *click_defs, StlClickRecord *click_r
     } else {
       xfree(cur_click_def.func);
     }
-    buf = (char *)click_recs[i].start;
+    buf = click_recs[i].start;
     cur_click_def = click_recs[i].def;
     if (!tabline && !(cur_click_def.type == kStlClickDisabled
                       || cur_click_def.type == kStlClickFuncRun)) {
@@ -2074,9 +2074,9 @@ int build_stl_str_hl(win_T *wp, char *out, size_t outlen, char *fmt, char *opt_n
         // to be moved backwards.
         if (stl_items[i].start >= trunc_end_p) {
           stl_items[i].start -= item_offset;
+        } else {
           // Anything inside the truncated area is set to start
           // at the `<` truncation character.
-        } else {
           stl_items[i].start = trunc_p;
         }
       }