diff --git a/examples/ZydisPerfTest.c b/examples/ZydisPerfTest.c
index 5344fd6..5783e89 100644
--- a/examples/ZydisPerfTest.c
+++ b/examples/ZydisPerfTest.c
@@ -393,7 +393,7 @@ int main(int argc, char** argv)
             }
 
             rewind(file);
-            if (fread(buffer, 1, length, file) != length)
+            if (fread(buffer, 1, length, file) != (size_t)length)
             {
                 fprintf(stderr, 
                     "Could not read %" PRIu64 " bytes from file \"%s\"", (uint64_t)length, &buf[0]);  
diff --git a/include/Zydis/Formatter.h b/include/Zydis/Formatter.h
index 9593b4a..92fea83 100644
--- a/include/Zydis/Formatter.h
+++ b/include/Zydis/Formatter.h
@@ -536,7 +536,7 @@ ZYDIS_EXPORT ZydisStatus ZydisFormatterSetHook(ZydisFormatter* formatter,
  * @return  A zydis status code.
  */
 ZYDIS_EXPORT ZydisStatus ZydisFormatterFormatInstruction(const ZydisFormatter* formatter, 
-    ZydisDecodedInstruction* instruction, char* buffer, size_t bufferLen);
+    const ZydisDecodedInstruction* instruction, char* buffer, size_t bufferLen);
 
 /**
  * @brief   Formats the given instruction and writes it into the output buffer.
@@ -551,7 +551,7 @@ ZYDIS_EXPORT ZydisStatus ZydisFormatterFormatInstruction(const ZydisFormatter* f
  * @return  A zydis status code.
  */
 ZYDIS_EXPORT ZydisStatus ZydisFormatterFormatInstructionEx(const ZydisFormatter* formatter, 
-    ZydisDecodedInstruction* instruction, char* buffer, size_t bufferLen, void* userData);
+    const ZydisDecodedInstruction* instruction, char* buffer, size_t bufferLen, void* userData);
 
 /* ============================================================================================== */
 
diff --git a/src/Formatter.c b/src/Formatter.c
index 3368b05..ed4607d 100644
--- a/src/Formatter.c
+++ b/src/Formatter.c
@@ -1074,13 +1074,13 @@ ZydisStatus ZydisFormatterSetHook(ZydisFormatter* formatter, ZydisFormatterHookT
 }
 
 ZydisStatus ZydisFormatterFormatInstruction(const ZydisFormatter* formatter, 
-    ZydisDecodedInstruction* instruction, char* buffer, size_t bufferLen)
+    const ZydisDecodedInstruction* instruction, char* buffer, size_t bufferLen)
 {
     return ZydisFormatterFormatInstructionEx(formatter, instruction, buffer, bufferLen, NULL);
 }
 
 ZydisStatus ZydisFormatterFormatInstructionEx(const ZydisFormatter* formatter, 
-    ZydisDecodedInstruction* instruction, char* buffer, size_t bufferLen, void* userData)
+    const ZydisDecodedInstruction* instruction, char* buffer, size_t bufferLen, void* userData)
 {
     if (!formatter || !instruction || !buffer || (bufferLen == 0))
     {