logo
Tags down

shadow

How can I show that assignment is not atomic?


By : Linux_Wangpeng
Date : July 30 2020, 11:00 AM
I wish did fix the issue. Grab the disassembly and then check the documentation for your architecture; on some machines you'll find even standard "non-atomic" operations (in terms of C++) are actually atomic when it hits the hardware (in terms of assembly).
With that said, your compiler will know what is and isn't safe and it is therefore a better idea to use the std::atomic template to make your code more portable across architectures. If you're on a platform that doesn't require anything special, it'll typically get optimised down to a primitive type anyway (putting memory ordering aside).
code :


Share : facebook icon twitter icon

Is compound assignment ^= atomic in C#?


By : user3167192
Date : March 29 2020, 07:55 AM
it fixes the issue As answered above, x^=1 is not atomic. Could you use Interlocked.Increment (which is atomic) and then, when reading, consider the value % 2?

Python: conversion of a iterated assignment with an atomic assignment using numpy is not working when matrix height >


By : user2519149
Date : March 29 2020, 07:55 AM
seems to work fine I get the problem!
I cast the matrix I to uint8 and so matrix I elements are between 0 and 255.

What does assignment mean to a C11 atomic?


By : bhag jathol
Date : March 29 2020, 07:55 AM
like below fixes the issue Operations on objects that are _Atomic qualified (and atomic_int is just a different writing for that) are guaranteed to have sequential consistency. You find that mentionned at the end of the semantics section for each of the operands. (And maybe the mention for assignment is missing.)
Your code is not correct at two places: initialization must use the ATOMIC_VAR_INIT macro (7.17.2.1), and memcpy is undefined (the sizes might not agree), although it probably will work on most of the architectures.
code :
tmp = mc + 4;                // Arithmetic
mc += 4;                // Arithmetic

C# Is value type assignment atomic?


By : user2145915
Date : March 29 2020, 07:55 AM
this will help Structs are value types. If you assign a struct to a variable/field/method parameter, the whole struct content will be copied from the source storage location to the storage location of the variable/field/method parameter (the storage location in each case being the size of the struct itself).
Copying a struct is not guaranteed to be an atomic operation. As written in the C# language specification:

Are assignment = and subtraction assignment -= atomic operations in C?


By : belrod
Date : March 29 2020, 07:55 AM
I hope this helps you . It depends on the implementation. By the standard, nothing is atomic in C. If you need atomic ops you can look at your compiler's builtins.
Related Posts Related Posts :
  • store strings in stable memory in c++
  • Why is static_cast used in QT's official document
  • iterator .end() from std::list returns "0xcdcdcdcdcdcdcdcd" but .begin() as expected
  • Is std::sqrt the same as sqrt in C++
  • Iterate through std::initializer_list
  • Codeblocks c++ code doesn't run in VS 19 (vector subscript out of range)
  • Why erase on std::vector promote iterator
  • how to destroy an object in C++
  • How to create Visual Studio 2015 solution from CMake
  • Using concepts for checking if a type T has a field F
  • constructor giving error: no matching function for call to
  • search top n% of a vector member C++
  • Is this reinterpret_cast problematic in principle, and/or in practice?
  • What is the following error doing? I do not see any error with the bounds
  • Two index's of an array have same memory adress
  • how do i avoid integer division in c++?
  • Setting value to enum
  • Properties of a pointer to a zero length array
  • Why the output is different how ever the formula is the same?
  • Restarting from the beginning using do while loops
  • Error: invalid initialization of reference of type
  • how to avoid to use memcpy to create a string
  • Copying the vector elements into std::array
  • Is there any class pointers in Perl in order to access member variables and functions?
  • Why the static variable is not set to 1000
  • Why can't a destructor have reference qualifiers?
  • How to print binary tree in horizontal way?
  • Comparison behavior of ' <' operator
  • Constructors in C++ Language
  • Why displayed value of b , c and y is different from my trace?
  • Undefined reference to `fftw_init_threads' while installing pHash library
  • Reading remapped hdd sectors
  • why the result is 1?
  • YouCompleteMe conf file for inspecting libraries header files without reporting the library errors
  • How CMake finds packages
  • Get UTC epoch time till start of current year in C++
  • access to iterator in lambda function of an algorithm cause me segmentation fault
  • How to prevent bool to int conversion in constructor?
  • std::map with keys that have no ordering
  • Different uses of noexcept
  • Invoking `constexpr` member function through reference - clang vs gcc
  • Why do I need to provide constructor implementation in header? C++
  • unsigned long cannot hold the correct number over 2,147,483,647
  • Take as input str, a string. Write a code which moves all ‘x’ from the string to its end.Print the value returned
  • How to compile C ++ code from Windows for Linux (Dev-Cpp)
  • rand with vector of strings in a multimap
  • How to get object type of pointer to non-static data member at compile time?
  • difference between *b= *b+1 and *b++
  • Can a core constant expression contain an ignored reinterpret_cast?
  • Adjusting CMake compiler commands to account for weirdness
  • How can I input a state to a variable of enum type in C++?
  • Reading from stream to initialize a read-only variable
  • Empty std::array<T, 0> doesn't have constexpr begin()?
  • Why references have types even though they are not objects?
  • Reverse of an array Hackerrank
  • Allocate more RAM to executable
  • VS2019 fatal error C1083: Cannot open compiler intermediate file: xxxx.ipdb: Not enough space
  • RAII and members if constructor throws?
  • C++ The correct way to multiply an integer and a double
  • how to convert const Uint8* to Uint8*
  • shadow
    Privacy Policy - Terms - Contact Us © voile276.org