fix warning about ignoring fread() return value

glslUtil.c

@@ -18,9 +18,14 @@ static char *loadFile(const char *fname)
         return NULL;
     char * buff = malloc(st.st_size + 1);
     FILE *fil = fopen(fname, "r");
-    fread(buff, st.st_size, 1, fil);
+    int bytes_read = fread(buff, st.st_size, 1, fil);
     fclose(fil);
     buff[st.st_size] = '\0';
+    if (bytes_read != st.st_size)
+    {
+        free(buff);
+        return NULL;
+    }
     return buff;
 }