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! Pull requests. 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. You just need to suppress the warning, and this will do it: This may offend your sensibilities, but it's very short and has no race conditions (as you'd have if you used &i). Is it suspicious or odd to stand by the gate of a GA airport watching the planes? To subscribe to this RSS feed, copy and paste this URL into your RSS reader. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. 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 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. /** Dynamically allocate a 2d (x*y) array of elements of size _size_ bytes. /** Dynamically allocate a 2d (x*y) array of elements of size _size_ bytes. The cast back to int * is not, though. Replacing broken pins/legs on a DIP IC package, How to handle a hobby that makes income in US. (void *)i Error: cast to 'void *' from smaller integer type 'int' PS: UBUNTUCLANG3.5 clang -O0 -std=gnu11 -march=native -lm -lpthread pagerank.c -o pagerank c pthreads 4 10.3k 2 21 2015-06-05 How do I check if a string represents a number (float or int)? Whats the grammar of "For those whose stories they are"? The point is (probably) that the value passed to the thread is an integer value, not really a 'void *'. Your first example is risky because you have to be very careful about the object lifetimes. Does a summoned creature play immediately after being summoned by a ready action? You can use any other pointer, or you can use (size_t), which is 64 bits. ", "? then converted back to pointer to void, and the result will compare Since all pointers on 64-bit Windows are 64 bits, you are growing the data size from 32 bits backto 64 bits. ^~~~~~~~~~~~~~~~~~~~~ For example, the main thread could wait for all of the other threads to end before terminating. The proper way is to cast it to another pointer type. Making statements based on opinion; back them up with references or personal experience. privacy statement. What does casting to void* does when passing arguments to variadic functions? I am compiling this program in linux gcc compiler.. And then assign it to the double variable. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Well occasionally send you account related emails. You can fix this error by replacing this line of code. this way I convert an int to a void* which is much better than converting a void* to an int. Disconnect between goals and daily tasksIs it me, or the industry? this way you won't get any warning. what does it mean to convert int to void* or vice versa? The bigint data type is intended for use when integer values might exceed the range that is supported by the int data type.. bigint fits between smallmoney and int in the data type precedence chart.. How can this new ban on drag possibly be considered constitutional? If the original pointer value represents an address of a byte in memory that does not satisfy the alignment requirement of the target type, then the resulting pointer value is unspecified. If your standard library (even if it is not C99) happens to provide these types - use them. See also this documentation.. From and Into are generally intended to be lossless, infalliable conversions.as on the other hand can discard data and lead to bugs in some situations, for example casting a u64 to a usize may truncate the value on a 32-bit host. You are getting warnings due to casting a void* to a type of a different size. How can this new ban on drag possibly be considered constitutional? The mapping in pointer<->integer casts is implementation defined, but the intent was that if the pointer type is large enough and isn't forcefully aligned (, But that's different. Why do academics stay as adjuncts for years rather than move around? ncdu: What's going on with this second size column? All float types are to be converted to double. Safe downcast may be done with dynamic_cast. @jackdoe: It's a waste of human life to write code that "you may need in the future". Therefore, you need to change it to long long instead of long in windows for 64 bits. The result is the same as implicit conversion from the enum's underlying type to the destination type. tialized" "-Wno-format" "-Wno-incompatible-pointer-types" "-Werror" "-dM" "-U_MSC_VER" "-D_TIMESPEC_DEFINED" "-D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_SECURE_NO_WA Making statements based on opinion; back them up with references or personal experience. I guess the other important fact is that the cast operator has higher precedence that the multiplication operator. 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. I have looked around and can't seem to find any information on how to do this. How to get the error message from the error code returned by GetLastError()? 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). If you are going to pass the address you typically need to exert some more control over the lifetime of the object. Infact I know several systems where that does not hold. Offline ImPer Westermark over 11 years ago in reply to Andy Neil Except that you sometimes stores an integer in the pointer itself. ^~~~~~~~~~~~~~~~~~~~ Why does flowing off the end of a non-void function without returning a value not produce a compiler error? Just re-enforcing the old behavior of Xcode 5.0 and earlier versions, that already cut away parts of the address by casting it to int, won't introduce any new bugs and avoids the need to learn and understand lots of implementation-internal cocos code. "I think what you should do is actually pass the address of the variable to the function" Not necessarily. Create an account to follow your favorite communities and start taking part in conversations. vegan) just to try it, does this inconvenience the caterers and staff? How to notate a grace note at the start of a bar with lilypond? So make sure you understand what you are doing! So reinterpret_cast has casted it to long type and then static_cast safely casts long to int, if you are ready do truncte the data. You can use a 64 bits integer instead howerver I usually use a function with the right prototype and I cast the function type : The text was updated successfully, but these errors were encountered: Find centralized, trusted content and collaborate around the technologies you use most. Why do small African island nations perform better than African continental nations, considering democracy and human development? Thanks for contributing an answer to Stack Overflow! Then i can continue compiling. @LearnCocos2D: so, how can i "overcome" the error without editing any not-my-code or in-library-file lines? How do I count the number of sentences in C using ". Losing bytes like thisis called 'truncation', and that's what the first warning is telling you. If your code has the chance to ever be ported to some platform where this doesn't hold, this won't work. "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. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. *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 . Or, they are all wrong. How Intuit democratizes AI development across teams through reusability. Only the following conversions can be done with static_cast, except when such conversions would cast away constness or volatility. LLNL's tutorial is bad and they should feel bad. Can I tell police to wait and call a lawyer when served with a search warrant? But then you need to cast your arguments inside your thread function which is quite unsafe cf. Euler: A baby on his lap, a cat on his back thats how he wrote his immortal works (origin? @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. . Put your define inside a bracket: without a problem. and how to print the thread id of 2d array argument? To avoid truncating your pointer, cast it to a type of identical size. I'm unfamiliar with XCode, but the solution should be something like follows: Most of the "solutions" above can lose part of the pointer address when casting to a smaller type. Asking for help, clarification, or responding to other answers. ncdu: What's going on with this second size column? Then I build my project, I get the error "Cast from pointer to smaller type 'int' loses information" in EAGLView.mm file (line 408) when 64-bit simulators (e.g. Issues. I'm using cocos2d-x-2.2.2. Noncompliant Code Example (memset())For historical reasons, certain C Standard functions accept an argument of type int and convert it to either unsigned char or plain char. The problem just occur with Xcode 5.1. 7.1 New Cast Operations The C++ standard defines new cast operations that provide finer control than previous cast operations. It's always a good practice to put your #define's in brackets to avoid such surprise. Thanks for contributing an answer to Stack Overflow! This answer is incorrect for the reasons that have already been mentioned in the comment of, Error "Cast from pointer to smaller type 'int' loses information" in EAGLView.mm when update Xcode to 5.1 (5B130a), http://en.wikipedia.org/wiki/64-bit_computing#64-bit_data_models, http://stackoverflow.com/questions/18913906/xcode-5-and-ios-7-architecture-and-valid-architectures, How Intuit democratizes AI development across teams through reusability. @kshegunov said in Number Type Cast: const void * x; int y = int (x); compiles just fine. "clang" "-Ilib\libopenvswitch.a.p" "-Ilib" "-I..\lib" "-I." If this is the data to a thread procedure, then you quite commonly want to pass by value.