OP said he doesn't want it. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. For a fairly recent compiler (that supports C99) you should not store or represent address as plain int value. Why don't we use the 7805 for car phone chargers? I hit this same problem in a project without C++11, and worked around it like this: Thanks for contributing an answer to Stack Overflow! If your standard library (even if it is not C99) happens to provide these types - use them. Find centralized, trusted content and collaborate around the technologies you use most. void *ptr; int n = (int)ptr; So in c++ i tried below int n = atoi (static_cast<const char*> (ptr)); This crashes when i run. Is a downhill scooter lighter than a downhill MTB with same performance? Therefore, you need to change it to long long instead of long in windows for 64 bits. Interpreting non-statistically significant results: Do we have "no evidence" or "insufficient evidence" to reject the null? (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 10.8k 2 21 2015-06-05 If int is no larger than pointer to void then one way to store the value is by simply copying the bytes: int i . Embedded hyperlinks in a thesis or research paper. and how to print the thread id of 2d array argument? Is "I didn't think it was serious" usually a good defence against "duty to rescue"? Episode about a group who book passage on a space ship controlled by an AI, who turns out to be a human who can't leave his ship? For example, if the pointers in a system are stored in 16 bits, but integers are stored in 8 bits, a total of 8 bits would be lost in the . The compiler issues the "cast from integer to pointer of different size" warning whenever the value of an integer is converted to a pointer, especially when the memory allocated to a pointer is smaller than the memory allocated to an integer data type. [Solved] Disabling "cast from pointer to smaller type | 9to5Answer property that any valid pointer to void can be converted to this type, 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. On a 64-bit Windows computer, 'long' is a 32-bit type, and all pointers are 64-bit types. I think the solution 3> should be the correct one. The error I'm getting is: error: cast from pointer to smaller type 'uint32_t' (aka 'unsigned int') loses information. For more information, see How to convert a byte array to an int, How to convert a string to a number, and How to convert between hexadecimal strings and numeric types. If the types are from the same inheritance tree, then you should either use dynamic_casts or even better, you should benefit from dynamic dispatching.. dynamic_cast is slightly better, but still should be avoided. In 64-bit programs, the size of the pointer is 64 bits, and cannot be put into the int type, which remains 32-bit in almost all systems. 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). What does casting to void* does when passing arguments to variadic functions? How to make compiler not show int to void pointer cast warnings, incompatible pointer types assigning to 'void (*)(void *)' from 'int (int *)'. That could create all kinds of trouble. 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, Short story about swapping bodies as a job; the person who hires the main character misuses his body. "Signpost" puzzle from Tatham's collection. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s). Don't pass your int as a void*, pass a int* to your int, so you can cast the void* to an int* and copy the dereferenced pointer to your int. again. cast to void *' from smaller integer type 'int-tdecu credit scoretdecu credit score Thank you all for your feedback. Which reverse polarity protection is better and why? /** Dynamically allocate a 2d (x*y) array of elements of size _size_ bytes. @DavidHeffernan I rephrased that sentence a little. Even if you are compiling your program for a 32-bit computer, you should fix your code to remove these warnings, to ensure your code is easily portable to 64-bit. It does not because. Thanks for contributing an answer to Stack Overflow! What differentiates living as mere roommates from living in a marriage-like relationship? cast to void *' from smaller integer type 'int this way I convert an int to a void* which is much better than converting a void* to an int. You can use any other pointer, or you can use (size_t), which is 64 bits. 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). Thus as a result it may be less error prone to generate a pointer dynamcially and use that. [Solved] Error "Cast from pointer to smaller type 'int' loses The only. There is no "correct" way to store a 64-bit pointer in an 32-bit integer. Can you still use Commanders Strike if the only attack available to forego is an attack against an ally? The reinterpret_cast makes the int the size of a pointer and the warning will stop. 1.6. Casting and Ranges of Variables AP CSAwesome Surely the solution is to change the type of ids from int to type that is sufficiently large to hold a pointer. Short story about swapping bodies as a job; the person who hires the main character misuses his body. Did the Golden Gate Bridge 'flatten' under the weight of 300,000 people in 1987? converted back to pointer to void, and the result will compare equal I'm working on a school project that involves porting a large piece of C++ code on an experimental piece of hardware. User without create permission can create a custom object from Managed package using Custom Rest API. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. If a negative integer value is converted to an unsigned type, the resulting value corresponds to its 2's complement bitwise representation (i.e., If the conversion is from a floating-point type to an integer type, the value is truncated (the decimal part is removed). Not the answer you're looking for? ', referring to the nuclear power plant in Ignalina, mean? We have to pass address of the variable to the function because in function definition argument is pointer variable. 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 pointer/reference to a derived class pointer/reference. What does 'They're at four. this way you won't get any warning. To learn more, see our tips on writing great answers. How to correctly cast a pointer to int in a 64-bit application? Is a downhill scooter lighter than a downhill MTB with same performance? How can I control PNP and NPN transistors together from one pin? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, @Dinesh: could you please 1) show us those. There exist two main syntaxes for generic type-casting: functional and c-like: 1 2 3 4 double x = 10.3; int y; y = int (x); // functional notation y = (int) x; // c-like cast notation The functionality of these generic forms of type-casting is enough for most needs with fundamental data types. 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. Content Discovery initiative April 13 update: Related questions using a Review our technical responses for the 2023 Developer Survey, Setting a buffer of char* with intermediate casting to int*. ERROR: incompatible integer to pointer conversion assigning to 'string' (aka 'char *') from 'int', error: cast to 'string' (aka 'char *') from smaller integer type 'int' [-Werror,-Wint-to-pointer-cast], error: incompatible integer to pointer conversion assigning to 'string' (aka 'char *') from 'int' C, warning: initialization of 'unsigned char' from 'uint8_t *' {aka 'unsigned char *'} makes integer from pointer without a cast [-Wint-conversion], Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. This rule is particularly true for integer values that originate from untrusted sources and are used in any of the following ways: Integer operands of any pointer arithmetic, including array indexing c printf() C , {} . Next, when doing pointer arithmetic, the addition operation will use the pointer's type to determine how many bytes to add to it when incrementing it. Explicit conversions (casts): Explicit conversions require a cast expression. Type conversions - cplusplus.com So, when you cast a (void*) to (long), you are losing 32 bits of data in the conversion. 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" (. I personally upvoted this answer because by it's first line of text it helped me to understand the reason of this strange error message and what am I, poor idiot, doing :D. Not valid on Windows 64 - long is still 32-bit but pointers are 64-bit. What does it mean to convert int to void* or vice versa? This is a fine way to pass integers to new pthreads, if that is what you need. c - Cast int to void* - Stack Overflow However, you are also casting the result of this operation to (void*). Again, all of the answers above missed the point badly. How to Cast a void* ponter to a char without a warning? c - How to cast an integer to void pointer? - Stack Overflow d=(double *) Hi, 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.