diff --git a/include/cstd.h b/include/cstd.h
index a0bc025c0..436594f71 100644
--- a/include/cstd.h
+++ b/include/cstd.h
@@ -56,6 +56,7 @@
 #include <signal.h>
 #include <assert.h>
 #include <stdarg.h>
+#include <ctype.h>
 
 #endif /* !__cplusplus */
 #endif /* CSTD_H */
diff --git a/src/hacklib.c b/src/hacklib.c
index 9513ca42b..1878bbbfe 100644
--- a/src/hacklib.c
+++ b/src/hacklib.c
@@ -5,6 +5,7 @@
 /* NetHack may be freely redistributed.  See license for details. */
 
 #include "hack.h" /* for config.h+extern.h */
+
 /*=
     Assorted 'small' utility routines.  They're virtually independent of
     NetHack, except that rounddiv may call panic().  setrandom calls one
@@ -947,4 +948,22 @@ unicodeval_to_utf8str(int uval, uint8 *buffer, size_t bufsz)
     return 1;
 }
 
+int
+case_insensitive_comp(const char *s1, const char *s2)
+{
+    uchar u1, u2;
+
+    for (;; s1++, s2++) {
+        u1 = (uchar) *s1;
+        if (isupper(u1))
+            u1 = (uchar) tolower(u1);
+        u2 = (uchar) *s2;
+        if (isupper(u2))
+            u2 = (uchar) tolower(u2);
+        if (u1 == '\0' || u1 != u2)
+            break;
+    }
+    return u1 - u2;
+}
+
 /*hacklib.c*/
diff --git a/src/mdlib.c b/src/mdlib.c
index 23827a812..f2aae69a7 100644
--- a/src/mdlib.c
+++ b/src/mdlib.c
@@ -28,7 +28,7 @@
 #include "flag.h"
 #include "dlb.h"
 #include "hacklib.h"
-#include <ctype.h>
+
 /* version information */
 #ifdef SHORT_FILENAMES
 #include "patchlev.h"
@@ -61,13 +61,6 @@ char *bannerc_string(char *, size_t, const char *) NONNULL NONNULLPTRS;
 int case_insensitive_comp(const char *, const char *) NONNULLPTRS;
 
 static void make_version(void);
-#if 0
-static char *eos(char *) NONNULL NONNULLARG1;
-#endif
-
-#if 0
-static char *mdlib_strsubst(char *, const char *, const char *);
-#endif
 
 #ifndef HAS_NO_MKSTEMP
 #ifdef _MSC_VER
@@ -420,35 +413,6 @@ mkstemp(char *template)
 #endif /* HAS_NO_MKSTEMP */
 #endif /* MAKEDEFS_C || FOR_RUNTIME */
 
-#if 0
-static char *
-eos(char *str)
-{
-    while (*str)
-        str++;
-    return str;
-}
-#endif
-
-#if 0
-static char *
-mdlib_strsubst(char *bp, const char *orig, const char *replacement)
-{
-    char *found, buf[BUFSZ];
-
-    if (bp) {
-        /* [this could be replaced by strNsubst(bp, orig, replacement, 1)] */
-        found = strstr(bp, orig);
-        if (found) {
-            Strcpy(buf, found + strlen(orig));
-            Strcpy(found, replacement);
-            Strcat(bp, buf);
-        }
-    }
-    return bp;
-}
-#endif
-
 static char save_bones_compat_buf[BUFSZ];
 
 static void
@@ -899,24 +863,6 @@ build_options(void)
 
 #undef STOREOPTTEXT
 
-int
-case_insensitive_comp(const char *s1, const char *s2)
-{
-    uchar u1, u2;
-
-    for (;; s1++, s2++) {
-        u1 = (uchar) *s1;
-        if (isupper(u1))
-            u1 = (uchar) tolower(u1);
-        u2 = (uchar) *s2;
-        if (isupper(u2))
-            u2 = (uchar) tolower(u2);
-        if (u1 == '\0' || u1 != u2)
-            break;
-    }
-    return u1 - u2;
-}
-
 void
 runtime_info_init(void)
 {
diff --git a/util/makedefs.c b/util/makedefs.c
index df3afd4ee..4b91193f1 100644
--- a/util/makedefs.c
+++ b/util/makedefs.c
@@ -23,7 +23,6 @@
 #include "dlb.h"
 #include "hacklib.h"
 
-#include <ctype.h>
 #ifdef MAC
 #if defined(__SC__) || defined(__MRC__) /* MPW compilers */
 #define MPWTOOL