This is not even remotely "the correct answer". ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
int, bigint, smallint, and tinyint (Transact-SQL) - SQL Server If this is the data to a thread procedure, then you quite commonly want to pass by value. How to correctly cast a pointer to int in a 64-bit application? Connect and share knowledge within a single location that is structured and easy to search. Don't do that. SQL Server does not automatically promote . 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. Bulk update symbol size units from mm to map units in rule-based symbology. 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. The reinterpret_cast makes the int the size of a pointer and the warning will stop. You cannot just cast the 32-bit variable to a pointer, because that pointer on a 64-bit machine is twice as long. use $(ARCHS_STANDARD_32_BIT) at Architecture instead of $(ARCHS_STANDARD). Euler: A baby on his lap, a cat on his back thats how he wrote his immortal works (origin?). Difficulties with estimation of epsilon-delta limit proof. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Identify those arcade games from a 1983 Brazilian music video. For the remaining integral types, the result is the value of the enum if it can be represented by the target type and unspecified otherwise. @Xax: Here's a fixed version, without the race condition: gist.github.com/depp/241d6f839b799042c409, gist.github.com/depp/3f04508a88a114734195, How Intuit democratizes AI development across teams through reusability. C / C++ Forums on Bytes.
c - How to cast an integer to void pointer? - Stack Overflow ^~~~~~~~~~~~~~~~~~~ @DietrichEpp can you explain what is race condition with using. } SCAN_END_SINGLE(ATTR) So the compiler is very picky here and the correct solution to make the code compile again and still let it show the exact same behavior like in Xcode 5.0 is to first cast to an integer type with a size that matches the one of a pointer and to then do a second cast to the int that we actually want: I am using size_t here, because it is always having the same size as a pointer, no matter the platform. I'm new to coding and am trying to implement a simple program on my own, that prompts the user the number of residents in an apt complex, the prompts the user to enter the names and apt numbers of each resident. Visit Microsoft Q&A to post new questions. You need to cast the void* pointer to a char* pointer - and then dereference that char* pointer to give you the char that it points to! Getting Command /bin/sh failed with exit code 65 Error with Xcode 5.1 .
cast to 'void *' from smaller integer type 'int' I recall there was a TreeNode(int) early on prior to 1.0 release I can't remember why I removed it, if I should felt it was easy enough to cast to (void*) or if it was because it created type inference conflict at the call site. If we want to get the exact value of 7/5 then we need explicit casting from int to float: Example: int x=7, y=5; For example, if you want to store a 'long' value into a simple integer then you can type cast 'long' to 'int'. warning C4311: 'type cast': pointer truncation from 'void *' to 'long' in ECPG test files. On all of them int is 32bit, not 16bit. It is easier to understand and write than any other assembly language. a cast of which the programmer should be aware of what (s)he is doing. The most general answer is - in no way. this question. what happens when we typecast normal variable to void* or any pointer variable? ../lib/odp-util.c:5665:7: note: expanded from macro 'SCAN_SINGLE'
What is "cast from integer to pointer of different size" warning? A nit: in your version, the cast to void * is unnecessary. Don't do that. Referring to N1570 7.20.1.4/p1 (Integer types capable of holding object pointers): The following type designates a signed integer type with the property Actions. Find centralized, trusted content and collaborate around the technologies you use most. Now, what happens when I run it with the thread sanitizer? Error while setting app icon and launch image in xcode 5.1. 1. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. 10) A prvalue of type pointer to void (possibly cv-qualified) can be converted to pointer to any object type. I have looked around and can't seem to find any information on how to do this. I'm using cocos2d-x-2.2.2. Connect and share knowledge within a single location that is structured and easy to search. You use the address-of operator & to do that int x = 10; void *pointer = &x; And in the function you get the value of the pointer by using the dereference operator *: int y = * ( (int *) pointer); Share Improve this answer Follow edited Apr 15, 2013 at 13:58 answered Apr 15, 2013 at 13:53 Some programmer dude 394k 35 393 602 1 If the original type is a void *, converting to an int may lose date on platforms where sizeof(void *) != sizeof(int) (which is true of LP64 programming model). How to make compiler not show int to void pointer cast warnings, incompatible pointer types assigning to 'void (*)(void *)' from 'int (int *)'. this way you won't get any warning. (int*)Pc = pa; After the execution of the above code all the three pointers, i.e., Pa, Pd, and Pc, point to the value 150. Infact I know several systems where that does not hold. For the Nozomi from Shinagawa to Osaka, say on a Saturday afternoon, would tickets/seats typically be available - or would you need to book? What Is the Difference Between 'Man' And 'Son of Man' in Num 23:19? Why does setupterm terminate the program? Staging Ground Beta 1 Recap, and Reviewers needed for Beta 2.
c - type casting integer to void* - Stack Overflow converted back to pointer to void, and the result will compare equal Did any DOS compatibility layers exist for any UNIX-like systems before DOS started to become outmoded? Fork 63. Your first example is risky because you have to be very careful about the object lifetimes. The code ((void*)ptr + 1) does not work, because the compiler has no idea what size "void" is, and therefore doesn't know how many bytes to add. Is it plausible for constructed languages to be used to affect thought and control or mold people towards desired outcomes?
B Programming Language | What is the History and Concept? Thanks for contributing an answer to Stack Overflow! To be honest, I think, clang is too restrictive here. with ids being an array of ints and touch being a pointer. Here is my code: I already tried (void*)M_TABLE_SIZE but then I get an error that I cannot use the * operator.
Fix for objc/45925 A pointer converted to an integer of sufficient size and back to the same pointer type is guaranteed to have its original value, otherwise the resulting pointer cannot be dereferenced safely ( the round-trip conversion in the opposite direction is not guaranteed [.]) How can this new ban on drag possibly be considered constitutional? However, I believe that even if the define was for the "65536", it would not be what @kaetzacoatl wanted. The difference between a and &a is the type. Please help me compile Chez Scheme. This page has been accessed 1,655,678 times. ../lib/odp-util.c:5601:9: note: expanded from macro 'SCAN_PUT' Replacing broken pins/legs on a DIP IC package, How to handle a hobby that makes income in US. Why is this sentence from The Great Gatsby grammatical? The program can be set in such a way to ask the user to inform the type of data and . Java Type Casting. If any, how can the original function works without errors if we just ignore the warning. what does it mean to convert int to void* or vice versa? Find centralized, trusted content and collaborate around the technologies you use most. Making statements based on opinion; back them up with references or personal experience. What I am trying to emphasis that conversion from int to pointer and back again can be frough with problems as you move from platform to platform. The pointer doesn't actually point to anything, but it's the result of an earlier cast from an integer to a pointer (e.g. ../lib/odp-util.c:5489:33: note: expanded from macro 'SCAN_PUT_ATTR' Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. Pull requests. SCAN_SINGLE("skb_priority(", uint32_t, u32, OVS_KEY_ATTR_PRIORITY); By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Why are Suriname, Belize, and Guinea-Bissau classified as "Small Island Developing States"?
How to correctly cast a pointer to int in a 64-bit application? By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Already on GitHub? Can Martian regolith be easily melted with microwaves?
How to correctly type cast (void*)? - social.msdn.microsoft.com Asking for help, clarification, or responding to other answers. There's no proper way to cast this to int in general case. *PATCH] platform/x86: hp-wmi: Fix cast to smaller integer type warning @ 2023-01-23 13:28 Hans de Goede 2023-01-23 13:56 ` Hans de Goede 0 siblings, 1 reply; 2+ messages in thread From: Hans de Goede @ 2023-01-23 13:28 UTC (permalink / raw) To: Mark Gross Cc: Hans de Goede, Andy Shevchenko, platform-driver-x86, kernel test robot Fix the following .
error: cast from 'void*' to 'int' loses precision - Stack Overflow 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;
Type Casting in C Language with Examples - Dot Net Tutorials Instead of using a long cast, you should cast to size_t. If you are going to pass the address you typically need to exert some more control over the lifetime of the object. If the object expression refers or points to is actually a base class subobject of an object of type D, the result refers to the enclosing object of type D. Otherwise, the behavior is undefined: When the target type is bool (possibly cv-qualified), the result is false if the original value is zero and true for all other values. If the sizes are different then endianess comes into play. to the original pointer: The following type designates an unsigned integer type with the Thanks for pointing that out. Floating-point conversions SCAN_PUT(ATTR, NULL); I think the solution 3> should be the correct one. Yeah, the tutorial is doing it wrong. Why is there a voltage on my HDMI and coaxial cables? There's no proper way to cast this to int in general case. You are getting warnings due to casting a void* to a type of a different size. - the incident has nothing to do with me; can I use this this way? It is done by the compiler on its own, without any external trigger from the user. Half your pointer will be garbage. Euler: A baby on his lap, a cat on his back thats how he wrote his immortal works (origin? In Java, there are two types of casting: Widening Casting (automatically) - converting a smaller type to a larger type size.
C - Type Casting - tutorialspoint.com By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. ^~~~~~~~~~~~~~~~~~~~
What does it mean to convert int to void* or vice versa? If you cast an int pointer int, you might get back a different integer. In the best case this will give the same results as the original code, with no advantages, but in the worst case it will fail in multiple catastrophic ways (type punning, endianness, less efficient, etc. It's an int type guaranteed to be big enough to contain a pointer. I don't see how anything bad can happen . Any help with this is appreciated. So, when you cast a (void*) to (long), you are losing 32 bits of data in the conversion. Converts between types using a combination of implicit and user-defined conversions. error: comparison between pointer and integer ('int' and 'string' (aka 'char *')), CS50 Caesar program is working but check50 says it isn't. Notifications. I have a function with prototype void* myFcn(void* arg) which is used as the starting point for a pthread. What Is the Difference Between 'Man' And 'Son of Man' in Num 23:19? This is an old C callback mechanism so you can't change that. That's probably going to be true for most platforms you will ever encounter, but it's not a guarantee; it's implementation-dependent. Pd = Pa; Similarly, Pc may be type cast to type int and assigned the value Pa. 1. Put your define inside a bracket: without a problem. Using printf with a pointer to float gives an error, Meaning of int (*) (int *) = 5 (or any integer value), Casting int to void* loses precision, and what is the solution in required cases, Acidity of alcohols and basicity of amines. */void **MatrixIB (unsigned long x, unsigned long y, int size){ void *ptr; void **returnPtr; register unsigned long i, j; returnPtr = (void **) malloc (x * sizeof(void *)); ptr = (void *) malloc (x * y * size); for (i=0, j=0; j
returnPtr[j] = (void *) (ptr + i); // <<< Compile Errors, Error1error C2036: 'void *' : unknown sizec:\temp\testone\lib\utils.c57, 2> returnPtr[j] = (void *) ((long*)ptr + i); // <<< No compile errors, 3> returnPtr[j] = (void *) ((char*)ptr + i); // <<< No compile errors. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Example: int x=7, y=5; float z; z=x/y; /*Here the value of z is 1*/. But you seem to suggest by your answer that the user can pass 5 to pthread_create and then perform the above cast to get it back. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, @Dinesh: could you please 1) show us those. And you can't pass a pointer to a stack based object from the other thread as it may no longer be valid. In such a case the programmer can use a void pointer to point to the location of the unknown data type. The int data type is the primary integer data type in SQL Server. All float types are to be converted to double. As was pointed out by Martin, this presumes that sizeof(void*)>=sizeof(int). AC Op-amp integrator with DC Gain Control in LTspice. Not the answer you're looking for? actually no, as int my be a smaller type than a pointer ;-) But, of course with int64_t it works fine. Issues. Use returnPtr[j] = (void *) ((long)ptr + i); ). Find centralized, trusted content and collaborate around the technologies you use most. How to correctly cast a pointer to int in a 64-bit application? Passing arguments to pthread_create - invalid conversion from void(*)() to void(*)(void*). Why does Mister Mxyzptlk need to have a weakness in the comics? Can I tell police to wait and call a lawyer when served with a search warrant? pthread passes the argument as a void*. static const void* M_OFFSET = (void*)64*1024; Since gcc compiles that you are performing arithmetic between void* and an int ( 1024 ). Remarks. For integer casts in specific, using into() signals that . Thanks for contributing an answer to Stack Overflow! SCAN_PUT_ATTR(key, ATTR, skey, FUNC); Find centralized, trusted content and collaborate around the technologies you use most. Are there tables of wastage rates for different fruit and veg? Based on the design of this function, which modification is right. In this case, casting the pointer back to an integer is meaningless, because . The nature of simulating nature: A Q&A with IBM Quantum researcher Dr. Jamie We've added a "Necessary cookies only" option to the cookie consent popup. The only alternative is really to take time and fix all 64-bit code issues, of which there may be some non-trivial issues. return ((void **) returnPtr);} /* Matrix() */. rev2023.3.3.43278. even though the compiler doesn't know you only ever pass myFcn to pthread_create in conjunction with an integer. But then you need to cast your arguments inside your thread function which is quite unsafe cf. The difference between the phonemes /p/ and /b/ in Japanese, Styling contours by colour and by line thickness in QGIS, AC Op-amp integrator with DC Gain Control in LTspice, Identify those arcade games from a 1983 Brazilian music video. How Intuit democratizes AI development across teams through reusability. @BlueMoon Thanks a lot! I would create a structure and pass that as void* to pthread_create. Note that it's not guaranteed that casting an, Generally this kind of type casting does not lead to any concern as long as the addresses are encoded using the same length as the "variable type" (. Cast Operations - Oracle 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. Java Type Casting (With Examples) - Programiz Making statements based on opinion; back them up with references or personal experience. Yesterday, I updated Xcode to the newest version (5.1 (5B130a)) to compatible with iOS 7.1. ../lib/odp-util.c:5834:5: error: cast to smaller integer type 'unsigned long' from 'void *' [-Werror,-Wvoid-pointer-to-int-cast] What happens if you typecast as unsigned first? property that any valid pointer to void can be converted to this type, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~. What is the purpose of this D-shaped ring at the base of the tongue on my hiking boots? Not the answer you're looking for? Can Martian regolith be easily melted with microwaves? Whats the grammar of "For those whose stories they are"? What is the correct method to cast an int to a void*? vegan) just to try it, does this inconvenience the caterers and staff? The nature of simulating nature: A Q&A with IBM Quantum researcher Dr. Jamie We've added a "Necessary cookies only" option to the cookie consent popup. x is a local variable and its lifetime ends as soon as control leaves the scope it was defined in. pthread create managing values generated in function (in c), Establishing TCP socket connection between PHP client and C server on Ubuntu. Only the following conversions can be done with static_cast, except when such conversions would cast away constness or volatility. "-I.." "-Iinclude\openflow" "-I..\include\openflow" "-Iinclude\openvswitch" "-I..\include\openvsw I'm trying to create a void* from an int. Please note that the error I am receiving is "cast to smaller integer type 'int' from 'string' (aka 'char *')" referencing line of code: while (isalpha(residents[i].name) == 0). Is pthread_join a must when using pthread in linux?