diff --git a/crypto/test/malloc.cc b/crypto/test/malloc.cc
index 898f2a7c..33f09721 100644
--- a/crypto/test/malloc.cc
+++ b/crypto/test/malloc.cc
@@ -44,21 +44,20 @@
 #include <new>
 
 
-/* This file defines overrides for the standard allocation functions that allow
- * a given allocation to be made to fail for testing. If the program is run
- * with MALLOC_NUMBER_TO_FAIL set to a base-10 number then that allocation will
- * return NULL. If MALLOC_BREAK_ON_FAIL is also defined then the allocation
- * will signal SIGTRAP rather than return NULL.
- *
- * This code is not thread safe. */
+// This file defines overrides for the standard allocation functions that allow
+// a given allocation to be made to fail for testing. If the program is run
+// with MALLOC_NUMBER_TO_FAIL set to a base-10 number then that allocation will
+// return NULL. If MALLOC_BREAK_ON_FAIL is also defined then the allocation
+// will signal SIGTRAP rather than return NULL.
+//
+// This code is not thread safe.
 
 static uint64_t current_malloc_count = 0;
 static uint64_t malloc_number_to_fail = 0;
-static char failure_enabled = 0, break_on_fail = 0;
-static int in_call = 0;
+static bool failure_enabled = false, break_on_fail = false, in_call = false;
 
 extern "C" {
-/* These are other names for the standard allocation functions. */
+// These are other names for the standard allocation functions.
 extern void *__libc_malloc(size_t size);
 extern void *__libc_calloc(size_t num_elems, size_t size);
 extern void *__libc_realloc(void *ptr, size_t size);
@@ -75,16 +74,15 @@ static void cpp_new_handler() {
   return;
 }
 
-/* should_fail_allocation returns true if the current allocation should fail. */
-static int should_fail_allocation() {
-  static int init = 0;
-  char should_fail;
+// should_fail_allocation returns true if the current allocation should fail.
+static bool should_fail_allocation() {
+  static bool init = false;
 
   if (in_call) {
-    return 0;
+    return false;
   }
 
-  in_call = 1;
+  in_call = true;
 
   if (!init) {
     const char *env = getenv("MALLOC_NUMBER_TO_FAIL");
@@ -92,22 +90,22 @@ static int should_fail_allocation() {
       char *endptr;
       malloc_number_to_fail = strtoull(env, &endptr, 10);
       if (*endptr == 0) {
-        failure_enabled = 1;
+        failure_enabled = true;
         atexit(exit_handler);
         std::set_new_handler(cpp_new_handler);
       }
     }
     break_on_fail = (NULL != getenv("MALLOC_BREAK_ON_FAIL"));
-    init = 1;
+    init = true;
   }
 
-  in_call = 0;
+  in_call = false;
 
   if (!failure_enabled) {
-    return 0;
+    return false;
   }
 
-  should_fail = (current_malloc_count == malloc_number_to_fail);
+  bool should_fail = (current_malloc_count == malloc_number_to_fail);
   current_malloc_count++;
 
   if (should_fail && break_on_fail) {