and how to print the thread id of 2d array argument? whether it was an actual problem is a different matter though. } SCAN_END_SINGLE(ATTR) How can this new ban on drag possibly be considered constitutional? To learn more, see our tips on writing great answers. Difficulties with estimation of epsilon-delta limit proof. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. What video game is Charlie playing in Poker Face S01E07? SCAN_PUT_ATTR(mask, ATTR, smask, FUNC); How create a simple program using threads in C? What can a lawyer do if the client wants him to be acquitted of everything despite serious evidence? Converting one datatype into another is known as type casting or, type-conversion. Making statements based on opinion; back them up with references or personal experience. The following behavior-changing defect reports were applied retroactively to previously published C++ standards. But this code pass the normal variable .. Identify those arcade games from a 1983 Brazilian music video, Relation between transaction data and transaction id, The difference between the phonemes /p/ and /b/ in Japanese. What does it mean to convert int to void* or vice versa? The result is implementation-defined and typically yields the numeric address of the byte in memory that the pointer pointers to. The main point is: a pointer has a platform dependent size. Note:You might receive a runtime exception if the pointer contains a value unsuitable for the context. In both cases, converting the pointer to an integer type that's too small to represent all pointer values is a bug. The reinterpret_cast makes the int the size of a pointer and the warning will stop. I need to convert the argument to an int for later use: The compiler (GCC version 4.2.4) returns the error: You can cast it to an intptr_t type. You can fix this error by replacing this line of code. Issues. Casting an open pointer to other pointer types and casting other pointer types to an open pointer does not result in a compile time error. eg. You can also convert values from one type to another explicitly using the cast operator (see Chapter 5 ): ( type_name) expression In the following example, the cast operator causes the division of one integer variable by another to be performed as a floating-point operation: int sum = 22, count = 5; double mean = (double)sum / count; Using indicator constraint with two variables. If your code has the chance to ever be ported to some platform where this doesn't hold, this won't work. However, you are also casting the result of this operation to (void*). In a 64bit build a pointer is 64bit (contrary to a 32bit build, where it is 32bit), while an int is 32bit, so this assignment stores a 64bit value in a 32bit storage, which may result in a loss of information. Maybe you can try this too. Taking the above declarations of A, D, ch of the . In this case, casting the pointer back to an integer is meaningless, because . For the second example you can make sure that sizeof(int) <= sizeof(void *) by using a static_assert -- this way at least you'll get a notice about it. If this is the data to a thread procedure, then you quite commonly want to pass by value. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. For example, the main thread could wait for all of the other threads to end before terminating. Do new devs get fired if they can't solve a certain bug? A long long would not work for 32bit systems and a long would not work for 64 bit Windows (while 64bit Unix and Unix-like systems like OS X use the LP64 data model, in which a long is 64bit, 64bit Windows uses the LLP64 data model, in which a long has a size of 32bit (http://en.wikipedia.org/wiki/64-bit_computing#64-bit_data_models)). This is not a conversion at all. How do I count the number of sentences in C using ". Passing arguments to pthread_create - invalid conversion from void(*)() to void(*)(void*). 7.1 New Cast Operations The C++ standard defines new cast operations that provide finer control than previous cast operations. Did any DOS compatibility layers exist for any UNIX-like systems before DOS started to become outmoded? The high-order 9 bits of the number are used to hold a flag value, and the result is converted back into a pointer. Is it possible to create a concave light? B programing language is a language based on basic combined programming or a BCPL, and it is the precursor of the C programming language. If you need to keep the returned address, just keep it as void*. The result is the same as implicit conversion from the enum's underlying type to the destination type. And in this context, it is very very very common to see programmers lazily type cast the. How to notate a grace note at the start of a bar with lilypond? Put your define inside a bracket: without a problem. This returns the first 32 bits of the pointer which may be the top or the bottom depending on big versus little endian, as comment #2 said. Unless you have a valid address at that value, you are going to invoke undefined behaviour when try to use that pointer. If it's anything like cocos2d-iphone v2.x and just based on this slice of code in a core class I wager it's safe to say that cocos2d-x 2.x also is not compatible with 64 bit code, and you can expect all kinds of issues (not just compile-time but also runtime). Typically, long or unsigned long is . When is casting void pointer needed in C? C99 standard library provides intptr_t and uintptr_t typedefs, which are supposed to be used whenever the need to perform such a cast comes about. "because the type "int" supports only -32768 ~ 32768" This is not true for any modern desktop or mobile OS or any OS that is targeted by cocos2d-x. ../lib/odp-util.c:5665:7: note: expanded from macro 'SCAN_SINGLE' Mutually exclusive execution using std::atomic? what happens when we typecast normal variable to void* or any pointer variable? Not the answer you're looking for? How to use Slater Type Orbitals as a basis functions in matrix method correctly? As Ferruccio said, int must be replaced with intptr_t to make the program meaningful. The problem just occur with Xcode 5.1. Implicit Type Conversion is also known as 'automatic type conversion'. This example is noncompliant on an implementation where pointers are 64 bits and unsigned integers are 32 bits because the result of converting the 64-bit ptr cannot be represented in the 32-bit integer type. You can use a 64 bits integer instead howerver I usually use a function with the right prototype and I cast the function type : *sound/soc/codecs/tlv320aic32x4.c:1202:18: warning: cast to smaller integer type 'enum aic32x4_type' from 'void *' @ 2022-04-22 9:48 kernel test robot 0 siblings, 0 . Thanks for contributing an answer to Stack Overflow! Yeah, the tutorial is doing it wrong. It was derived from the BCPL, and the name of the b language is possibly from the BCPL contraction. Connect and share knowledge within a single location that is structured and easy to search. To learn more, see our tips on writing great answers. static_cast on the other hand should deny your stripping away the const qualifier. The difference between the phonemes /p/ and /b/ in Japanese, Styling contours by colour and by line thickness in QGIS. converted back to pointer to void, and the result will compare equal Can I tell police to wait and call a lawyer when served with a search warrant? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, You should be doing int x = *((int *)arg); You are casting from void * to int that is why you get the warning. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. I guess the other important fact is that the cast operator has higher precedence that the multiplication operator. Anw, the project still build and run normally when i use Xcode 5.0 with iOS 7.0. Wrong. This is a fine way to pass integers to new pthreads, if that is what you need. If you preorder a special airline meal (e.g. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. ../lib/odp-util.c:5601:9: note: expanded from macro 'SCAN_PUT' Don't do that. Linear regulator thermal information missing in datasheet. Put your define inside a bracket: #define M_TABLE_SIZE (64*1024) Now, you can do: static const void* M_OFFSET = (void*) M_TABLE_SIZE; without a problem. My code is GPL licensed, can I issue a license to have my code be distributed in a specific MIT licensed project? Use #include
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