diff --git a/libm/Android.bp b/libm/Android.bp
index 09d8535..00d90a0 100644
--- a/libm/Android.bp
+++ b/libm/Android.bp
@@ -199,11 +199,6 @@
         "upstream-netbsd/lib/libm/complex/ctanhl.c",
         "upstream-netbsd/lib/libm/complex/ctanl.c",
 
-        // TODO: this comes from from upstream's libc, not libm, but it's an
-        // implementation detail that should have hidden visibility, so it needs
-        // to be in whatever library the math code is in.
-        "digittoint.c",
-
         // Functionality not in the BSDs.
         "significandl.c",
         "fake_long_double.c",
diff --git a/libm/digittoint.c b/libm/digittoint.c
deleted file mode 100644
index 1824788..0000000
--- a/libm/digittoint.c
+++ /dev/null
@@ -1,46 +0,0 @@
-/*-
- * Copyright (c) 2007 David Schultz
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * $FreeBSD$
- */
-
-#include <sys/cdefs.h>
-
-/* digittoint is in the FreeBSD C library, but implemented in terms of locale stuff. */
-__LIBC_HIDDEN__ int digittoint(char ch) {
-  int d = ch - '0';
-  if ((unsigned) d < 10) {
-    return d;
-  }
-  d = ch - 'a';
-  if ((unsigned) d < 6) {
-    return d + 10;
-  }
-  d = ch - 'A';
-  if ((unsigned) d < 6) {
-    return d + 10;
-  }
-  return -1;
-}
diff --git a/libm/freebsd-compat.h b/libm/freebsd-compat.h
index 7accc55..a3c7cd4 100644
--- a/libm/freebsd-compat.h
+++ b/libm/freebsd-compat.h
@@ -27,18 +27,12 @@
 #define __strong_reference(sym,aliassym) \
     extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
 
-#define __warn_references(sym,msg) /* ignored */
-
-// digittoint is in BSD's <ctype.h>, but not ours, so we have a secret
-// implementation in libm. We reuse parts of libm in the NDK's
-// libandroid_support, where it's a static library, so we want all our
-// "hidden" functions start with a double underscore --- being HIDDEN
-// in the ELF sense is not sufficient.
-#define digittoint __libm_digittoint
-int digittoint(char ch);
-
-// Similarly rename _scan_nan.
-#define _scan_nan __libm_scan_nan
+// digittoint is in BSD's <ctype.h> but not ours.
+#include <ctype.h>
+static inline int digittoint(char ch) {
+  if (!isxdigit(ch)) return -1;
+  return isdigit(ch) ? (ch - '0') : (_tolower(ch) - 'a');
+}
 
 // FreeBSD exports these in <math.h> but we don't.
 double cospi(double);