Questions tagged [c++]
C++ is a general-purpose programming language. Use this tag for questions about/utilizing C++. Do not also tag questions with [c] unless you have a good reason. C and C++ are different languages. Use a versioned tag such as [c++11], [c++20] etc. for questions specific to a standard revision.
122
questions
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IntelliSense reports that identifier "size_t" is undefined for standards > C++03
I use VS Code with Microsoft's C/C++ extension, which includes IntelliSense. Whenever I use size_t, it is not recognized by IntelliSense. I am aware that it isn’t a requirement in the C++ standard ...
-1
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0
answers
15
views
What language would you reccommend for building a UI to access and manipulate large SQL databases? (Why? Benefits/Drawbacks?)) [closed]
I'm fairly new to coding and have been learning and building a personal archival database using SQL over the past few months. However, I would also like to develop a simple (at first) UI to use for ...
1
vote
1
answer
28
views
Why are types escaping namespace when included after vector header?
If I compile this minimized example with clang++:
#include <system_error>
#include <vector>
namespace MyNamespace {
namespace ffi {
#include <sys/types.h>
}
void example() {
...
- 1,931
-4
votes
0
answers
25
views
std::vector::erase() is not erasing windows and only erasing last element [closed]
This is the broken output
void WindowManager::checkWindowsForCloseRequest()
{
for (auto window = windowStack.begin(); window != windowStack.end();)
{
if (window->shouldWindowClose())...
- 1
0
votes
1
answer
21
views
Boost Beast Websocket verify client certificate more than once on connection
I have a Boost Beast asio based websocket server, which (in abbreviated form) starts like this
ssl_context_.set_options(
boost::asio::ssl::context::default_workarounds |
boost::asio::ssl::...
- 1,354
0
votes
1
answer
36
views
Initializing a vector with a class that has a pass-by-reference constructor parameter and saves that reference as a member
I'm trying intending to create a single instance of a type that gets shared among the items in a vector. Each of the vector's item types requires a pass-by-reference parameter in the constructor but I ...
- 126
0
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0
answers
25
views
How can I use VSCode with CMake and have different targets each with a different architecture and toolchain?
I'm working on a project with Visual Studio Code and CMake where I'm compiling / cross-compiling different targets for different platforms. Currently the project has three platforms, each of which ...
- 2,359
0
votes
0
answers
15
views
How to Determine if a Point is Occluded by a Mesh in Vulkan Without Ray Tracing? [closed]
I'm working on a Vulkan application where I need to determine if a specific 3D point is occluded by any of several triangular meshes. The meshes are defined using vertex and index buffers. I'm ...
0
votes
0
answers
20
views
How can I get the values from Shell Property 'System.ItemAuthors' as a string array in C#?
I’m at a complete loss on how to do this. I’ll preface by saying I’m able to get many shell properties for a file when they are of type uint64, uint32, DateTime, string, etc. as the example code shows....
- 73
0
votes
1
answer
40
views
Class member function returning another class: works for getting a class variable, but not for setting a class variable
Somewhere there seems to be an implied const that is not allowing getSubsiaryClass() when changing a variable member of the SubsidiaryClass, but it works fine for reading a variable. It isn't a ...
- 11
1
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0
answers
25
views
C++ Image color reduction error diffusion not working
I'm trying to implement the Floyd-Steinberg error diffusion algorithm as seen on this blog and plenty of other sources and I cannot figure out what's gone wrong with my code for the life of me.
The ...
- 11
3
votes
0
answers
46
views
Why are non-type template parameters limited to structural types?
When using non-type template parameters, the non-type parameter must be 'structural' per the C++ standard. Classes with private data members are not structural. However, sometimes it is convenient to ...
- 653
0
votes
0
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24
views
DLL Injection Hook Not Working in WPF Application
i am student studying reverse engineering.
These days, I am learning API Hook using DLL Injector
I made personal DLL Injector using C# WPF and C++/CLI
also i have created a DLL that hooks the send ...
- 1
2
votes
0
answers
39
views
Inaccurate compile-time computation of Fibonacci sequence in a recursive lambda
Below is a recursive lambda expression that can compute the values of Fibonacci sequence both in runtime and during constant evaluation:
auto fib = [](this auto && f, auto && p) {
...
- 19.3k
-5
votes
0
answers
34
views
How can instancing make this so much slower? [closed]
I'm drawing many copies of the same model. I can draw them by pushing a different uniform matrix for each one, or I can push a buffer full of matrices once and draw them with instancing. Why would the ...
- 1
0
votes
2
answers
66
views
Does a deque maintain its capacity even if emptied completely?
I wanted to test if a deque<> does free its chunks if it is completely emptied:
#include <iostream>
#include <deque>
using namespace std;
uint64_t nAllocs = 0, nFrees = 0;
void *...
-3
votes
0
answers
75
views
How do I get rid of this blue directory text that crams into everything else? Did I install C++ wrong, I installed MSYS2 aswell
The simple code that I ran:
I tried running, debugging, rewriting the code. I thought it would eventually fix itself, but it keeps spewing this out.
When I try it in a Command Prompt, it works as I ...
- 1
0
votes
0
answers
21
views
Giving application window active focus when opening a file
In the documentation for QWidget::activateWindow() function, the following is said:
... On Windows, if you are calling this when the application is not
currently the active one then it will not make ...
- 405
-2
votes
0
answers
37
views
Command exited with non-zero status 124
Given two integers n and x, find the number of triplets (a,b,c) of positive integers such that ab+ac+bc ≤ n and a+b+c ≤ x.
a,b,c are greater than 1. (c is k in my program):
#include <iostream>
...
- 17
0
votes
1
answer
71
views
Synchronize three Threads in C++ one after the other
This is in continuation to this really nice one: https://stackoverflow.com/a/33500554/22598822. That post was for the sequence (t1 & t2) --> t3. Let's say I have a program running, and there ...
- 23
2
votes
1
answer
75
views
explicit deleted constructors - does this matter?
When marking a constructor as deleted, i.e.
class MyClass {
// ...
MyClass(int x) = delete;
// ...
};
is there any effect to marking the deleted constructor as explicit? i.e.
...
- 127k
-2
votes
0
answers
49
views
What does "+ +" (with space between + operators) do in C++? [duplicate]
The following code:
float a = 1.5;
float b = a + + 1.2;
compiles and actually returns 2.7 for b. Why does it compile, shouldn't the extraneous + be flagged as a syntax error?
It compiles on several ...
- 15
-2
votes
0
answers
20
views
How do I create CRUD in C++ and connect it to a database. A sample code or link to specific Youtube tutorial will be helpful. Thank you [closed]
I do not how to Create, Read, Update, and Delete database in C++
I tried to install mysql on my computer and I cannot connect it.
My laptop's operating system is windows. I am finding it difficult to ...
-13
votes
0
answers
66
views
EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x00007ff8ed191184, pid=51412, tid=0x0000000000009a34 [closed]
I am writing protection for the maincraft cheat in the form of a native and when I added lazy importer I started having such errors
# A fatal error has been detected by the Java Runtime Environment:
#
...
-2
votes
0
answers
18
views
Qt6 QSGTexture not shown inside QQuickItem using custom shader classes
I try to show a simple texture through opengl and Qt6 using custom shader classes.
I created a QQuickItem which uses the updatePaintNode override to apply the QSGTexture to the custom Shader.
When I ...
- 1
-10
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0
answers
59
views
Chinese character turns into �� or @@ or just nothing [closed]
For example:
In run and debug:
In terminal:
When I input any Chinese, the debugging interface will show that the value of str1 is �� or @@ or just nothing, and it's a little unstable (but � is ...
1
vote
0
answers
33
views
How do I create a User Customizable popup menu from an existing CMenu?
I use MFCs CMenu to create right-click popup menus for many user commands (C++ using VS 2022). Is there already a framework for allowing user customization of these popup menus? Meaning the user will ...
- 11
-1
votes
1
answer
28
views
getting "expression list treated as compound expression in functional cast" CE, but everything looks just fine
I tried building this:
whole code (unordered_map.h): https://pastebin.com/u9aMaqRp
test: https://pastebin.com/KqrKwNt0
and got a CE out of nowhere...?
getting a strange compilation error while ...
-2
votes
0
answers
55
views
my code is showing wrong output in VS Code what should I do?
My code is showing wrong output in VS Code of my system whereas in online compiler and VS Code of other system it is working correctly how can i fix this issue.
Here is the code below
#include <...
0
votes
0
answers
9
views
Create nvblox depth image from sensor message pointcloud2
I have a rosbag2 with sensor_msgs/msg/PointCloud2 messages.
I am using Nvblox.
First I would like to ask if there is any way to create a depth image from the point cloud data.
Second I would like to ...
- 1