diff --git a/expat/CMakeLists.txt b/expat/CMakeLists.txt
index 5f59da71..210fa82c 100644
--- a/expat/CMakeLists.txt
+++ b/expat/CMakeLists.txt
@@ -687,6 +687,10 @@ if(EXPAT_BUILD_TESTS)
             target_link_libraries(${_target} ${LIB_BSD})
         endif()
     endforeach()
+
+    add_executable(benchmark tests/benchmark/benchmark.c)
+    set_property(TARGET benchmark PROPERTY RUNTIME_OUTPUT_DIRECTORY tests/benchmark)
+    target_link_libraries(benchmark expat)
 endif()
 
 #
diff --git a/expat/tests/benchmark/benchmark.c b/expat/tests/benchmark/benchmark.c
index 2c4eb78e..a611c571 100644
--- a/expat/tests/benchmark/benchmark.c
+++ b/expat/tests/benchmark/benchmark.c
@@ -33,6 +33,8 @@
 */
 
 #include <sys/stat.h>
+#include <assert.h>
+#include <stddef.h> // ptrdiff_t
 #include <stdlib.h>
 #include <stdio.h>
 #include <time.h>
@@ -62,7 +64,8 @@ main(int argc, char *argv[]) {
   char *XMLBuf, *XMLBufEnd, *XMLBufPtr;
   FILE *fd;
   struct stat fileAttr;
-  int nrOfLoops, bufferSize, fileSize, i, isFinal;
+  int nrOfLoops, bufferSize, i, isFinal;
+  size_t fileSize;
   int j = 0, ns = 0;
   clock_t tstart, tend;
   double cpuTime = 0.0;
@@ -114,12 +117,13 @@ main(int argc, char *argv[]) {
     isFinal = 0;
     tstart = clock();
     do {
-      int parseBufferSize = XMLBufEnd - XMLBufPtr;
-      if (parseBufferSize <= bufferSize)
+      ptrdiff_t parseBufferSize = XMLBufEnd - XMLBufPtr;
+      if (parseBufferSize <= (ptrdiff_t)bufferSize)
         isFinal = 1;
       else
         parseBufferSize = bufferSize;
-      if (! XML_Parse(parser, XMLBufPtr, parseBufferSize, isFinal)) {
+      assert(parseBufferSize <= (ptrdiff_t)bufferSize);
+      if (! XML_Parse(parser, XMLBufPtr, (int)parseBufferSize, isFinal)) {
         fprintf(stderr,
                 "error '%" XML_FMT_STR "' at line %" XML_FMT_INT_MOD
                 "u character %" XML_FMT_INT_MOD "u\n",