diff --git a/src/cmd/smlrc/cgmips.c b/src/cmd/smlrc/cgmips.c
index 685e60f..7eb4a41 100644
--- a/src/cmd/smlrc/cgmips.c
+++ b/src/cmd/smlrc/cgmips.c
@@ -1210,7 +1210,7 @@ void GenPrep(int* idx)
         xor = '<' ^ '>'; break;
       case tokLEQ:
       case tokGEQ:
-        xor = tokLEQ ^ tokGEQ; break;
+        xor = (int)tokLEQ ^ tokGEQ; break;
       case tokULess:
       case tokUGreater:
         xor = tokULess ^ tokUGreater; break;
@@ -2261,4 +2261,3 @@ void GenFin(void)
   }
 #endif
 }
-
diff --git a/src/cmd/smlrc/lb.c b/src/cmd/smlrc/lb.c
index 47a9854..45d4762 100644
--- a/src/cmd/smlrc/lb.c
+++ b/src/cmd/smlrc/lb.c
@@ -152,10 +152,10 @@ int atoi(char* s)
   return r;
 }
 
-unsigned strlen(char* str)
+unsigned strlen(const char* str)
 {
 #ifndef __SMALLER_C_16__
-  char* s;
+  const char* s;
 
   if (str == NULL)
     return 0;
@@ -175,7 +175,7 @@ unsigned strlen(char* str)
 #endif
 }
 
-char* strcpy(char* dst, char* src)
+char* strcpy(char* dst, const char* src)
 {
 #ifndef __SMALLER_C_16__
   char* p = dst;
@@ -196,7 +196,7 @@ char* strcpy(char* dst, char* src)
   return dst;
 }
 
-char* strchr(char* s, int c)
+char* strchr(const char* s, int c)
 {
 #ifndef __SMALLER_C_16__
   char ch = c;
@@ -204,12 +204,12 @@ char* strchr(char* s, int c)
   while (*s)
   {
     if (*s == ch)
-      return s;
+      return (char*)s;
     ++s;
   }
 
   if (!ch)
-    return s;
+    return (char*)s;
 
   return NULL;
 #else
@@ -230,7 +230,7 @@ char* strchr(char* s, int c)
 #endif
 }
 
-int strcmp(char* s1, char* s2)
+int strcmp(const char* s1, const char* s2)
 {
 #ifndef __SMALLER_C_16__
   while (*s1 == *s2)
@@ -259,7 +259,7 @@ int strcmp(char* s1, char* s2)
 #endif
 }
 
-int strncmp(char* s1, char* s2, unsigned n)
+int strncmp(const char* s1, const char* s2, unsigned n)
 {
 #ifndef __SMALLER_C_16__
   if (!n)
@@ -294,11 +294,11 @@ int strncmp(char* s1, char* s2, unsigned n)
 #endif
 }
 
-void* memmove(void* dst, void* src, unsigned n)
+void* memmove(void* dst, const void* src, unsigned n)
 {
 #ifndef __SMALLER_C_16__
   char* d = dst;
-  char* s = src;
+  const char* s = src;
 
   if (s < d)
   {
@@ -337,11 +337,11 @@ void* memmove(void* dst, void* src, unsigned n)
   return dst;
 }
 
-void* memcpy(void* dst, void* src, unsigned n)
+void* memcpy(void* dst, const void* src, unsigned n)
 {
 #ifndef __SMALLER_C_16__
   char* p1 = dst;
-  char* p2 = src;
+  const char* p2 = src;
 
   while (n--)
     *p1++ = *p2++;
@@ -380,11 +380,11 @@ void* memset(void* s, int c, unsigned n)
 }
 
 #ifdef __SMALLER_C_32__
-int memcmp(void* s1, void* s2, unsigned n)
+int memcmp(const void* s1, const void* s2, unsigned n)
 {
   if (n)
   {
-    unsigned char *p1 = s1, *p2 = s2;
+    unsigned const char *p1 = s1, *p2 = s2;
     do
     {
       if (*p1++ != *p2++)
@@ -591,23 +591,23 @@ int __vsprintf__(char** buf, FILE* stream, char* fmt, void* vl)
   return cnt;
 }
 
-int vprintf(char* fmt, void* vl)
+int vprintf(const char* fmt, void* vl)
 {
-  return __vsprintf__(NULL, NULL, fmt, vl);
+  return __vsprintf__(NULL, NULL, (char*)fmt, vl);
 }
 
-int printf(char* fmt, ...)
+int printf(const char* fmt, ...)
 {
   void** pp = (void**)&fmt;
   return vprintf(fmt, pp + 1);
 }
 
-int vsprintf(char* buf, char* fmt, void* vl)
+int vsprintf(char* buf, const char* fmt, void* vl)
 {
-  return __vsprintf__(&buf, NULL, fmt, vl);
+  return __vsprintf__(&buf, NULL, (char*)fmt, vl);
 }
 
-int sprintf(char* buf, char* fmt, ...)
+int sprintf(char* buf, const char* fmt, ...)
 {
   void** pp = (void**)&fmt;
   return vsprintf(buf, fmt, pp + 1);
@@ -1755,4 +1755,3 @@ float __gesf2(float a, float b)
 #endif
 
 #endif /*__APPLE__*/
-
diff --git a/src/cmd/smlrc/smlrc.c b/src/cmd/smlrc/smlrc.c
index 97f3daa..ea3ea5f 100644
--- a/src/cmd/smlrc/smlrc.c
+++ b/src/cmd/smlrc/smlrc.c
@@ -124,15 +124,15 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 void exit(int);
 int atoi(char*);
 
-size_t strlen(char*);
-char* strcpy(char*, char*);
-char* strchr(char*, int);
-int strcmp(char*, char*);
-int strncmp(char*, char*, size_t);
-void* memmove(void*, void*, size_t);
-void* memcpy(void*, void*, size_t);
+size_t strlen(const char*);
+char* strcpy(char*, const char*);
+char* strchr(const char*, int);
+int strcmp(const char*, const char*);
+int strncmp(const char*, const char*, size_t);
+void* memmove(void*, const void*, size_t);
+void* memcpy(void*, const void*, size_t);
 void* memset(void*, int, size_t);
-int memcmp(void*, void*, size_t);
+int memcmp(const void*, const void*, size_t);
 
 int isspace(int);
 int isdigit(int);
@@ -148,13 +148,13 @@ int fputc(int, FILE*);
 int fgetc(FILE*);
 int puts(char*);
 int fputs(char*, FILE*);
-int sprintf(char*, char*, ...);
+int sprintf(char*, const char*, ...);
 //int vsprintf(char*, char*, va_list);
-int vsprintf(char*, char*, void*);
-int printf(char*, ...);
-int fprintf(FILE*, char*, ...);
+int vsprintf(char*, const char*, void*);
+int printf(const char*, ...);
+int fprintf(FILE*, const char*, ...);
 //int vprintf(char*, va_list);
-int vprintf(char*, void*);
+int vprintf(const char*, void*);
 //int vfprintf(FILE*, char*, va_list);
 int vfprintf(FILE*, char*, void*);
 struct fpos_t_
@@ -8938,7 +8938,7 @@ int ParseStatement(int tok, int BrkCntTarget[2], int casesIdx)
         UndoNonLabelIdents(undoIdents); // remove all identifier names, except those of labels
         SyntaxStackCnt = undoSymbolsPtr; // remove all params and locals
         CurFxnLocalOfs = undoLocalOfs; // destroy on-stack local variables
-      } 
+      }
 #endif
     }
     else if (tok == tokBreak)
@@ -9470,4 +9470,3 @@ int main(int argc, char** argv)
 
   return 0;
 }
-
diff --git a/src/libc/runtime/Makefile b/src/libc/runtime/Makefile
index 3cb38a9..7906f32 100644
--- a/src/libc/runtime/Makefile
+++ b/src/libc/runtime/Makefile
@@ -29,6 +29,7 @@ OBJS            = adddf3.o \
                   extendsfdf2.o \
                   fixdfsi.o \
                   fixsfsi.o \
+                  fixunssfsi.o \
                   floatsidf.o \
                   floatsisf.o \
                   floatunsisf.o \
diff --git a/src/libc/runtime/fixunssfsi.c b/src/libc/runtime/fixunssfsi.c
new file mode 100644
index 0000000..738c1bb
--- /dev/null
+++ b/src/libc/runtime/fixunssfsi.c
@@ -0,0 +1,26 @@
+//===-- fixunssfsi.c - Implement __fixunssfsi -----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __fixunssfsi for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#define SINGLE_PRECISION
+#include "fp_lib.h"
+typedef su_int fixuint_t;
+#include "fp_fixuint_impl.inc"
+
+COMPILER_RT_ABI su_int __fixunssfsi(fp_t a) { return __fixuint(a); }
+
+#if defined(__ARM_EABI__)
+#if defined(COMPILER_RT_ARMHF_TARGET)
+AEABI_RTABI su_int __aeabi_f2uiz(fp_t a) { return __fixunssfsi(a); }
+#else
+COMPILER_RT_ALIAS(__fixunssfsi, __aeabi_f2uiz)
+#endif
+#endif
diff --git a/src/libc/runtime/fp_fixuint_impl.inc b/src/libc/runtime/fp_fixuint_impl.inc
new file mode 100644
index 0000000..cb2bf54
--- /dev/null
+++ b/src/libc/runtime/fp_fixuint_impl.inc
@@ -0,0 +1,38 @@
+//===-- lib/fixdfsi.c - Double-precision -> integer conversion ----*- C -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements float to unsigned integer conversion for the
+// compiler-rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "fp_lib.h"
+
+static __inline fixuint_t __fixuint(fp_t a) {
+  // Break a into sign, exponent, significand parts.
+  const rep_t aRep = toRep(a);
+  const rep_t aAbs = aRep & absMask;
+  const int sign = aRep & signBit ? -1 : 1;
+  const int exponent = (aAbs >> significandBits) - exponentBias;
+  const rep_t significand = (aAbs & significandMask) | implicitBit;
+
+  // If either the value or the exponent is negative, the result is zero.
+  if (sign == -1 || exponent < 0)
+    return 0;
+
+  // If the value is too large for the integer type, saturate.
+  if ((unsigned)exponent >= sizeof(fixuint_t) * CHAR_BIT)
+    return ~(fixuint_t)0;
+
+  // If 0 <= exponent < significandBits, right shift to get the result.
+  // Otherwise, shift left.
+  if (exponent < significandBits)
+    return significand >> (significandBits - exponent);
+  else
+    return (fixuint_t)significand << (exponent - significandBits);
+}