Using boost/python on Windows - c++

I'm trying to get into C++-extensions for python, with boost/python.
I've downloaded boost 1_73 and installed it by calling bootstrap and then b2 --with-python
In Visual Studio, i've included the compiler include path (the boost directory) and linker library paths (/stage/lib/) that the output of b2 tells me to.
Now I get the compiler error LNK1104 cannot open file 'boost_python37-vc141-mt-x64-1_73.lib'. I can't find any information about this specific error. For everything similar there is only the suggestion to add the above mentioned paths.
The code I'm trying to compile is just the hello world example supplied with boost.
Any ideas?

First check that file exists somewhere in your filesystem. If it doesn't, you may have accidentally built it against a different version (i.e. not 141) of the VC runtime. (This has happened to me when I've had multiple runtimes installed.)
If you do have the file, then you just need to ensure that the path is in the link settings section of your project config.

Related

Missing libgcc_s_seh-1.dll starting the .exe on Windows

Intro
I have a CMake-based C++ project. Until now I build and ran the project via CLion. Everything worked fine until I tried to run the .exe-file directly (not via CLion).
Problem
When I navigate to the cmake build directory in order to start my program via the executable file, it fails with the following message in the popup: Cannot continue the code execution because libgcc_s so-1.dll was not found. Reinstalling the program may resolve the issue.
I have the following questions
If I interpret the error message correctly, then this dll is missing on my computer. So I ask myself, why does my program still work when I start it via the development environment (CLion), although the error message expressly states that the source code requires this dll?
Is it the fault of my application/source code that the error appears or rather the current state of my computer? If the former, how can I prevent this error from appearing for other users?
What is the best way to fix this error? It's obvious that I need to download this dll, but where is the best place to put it (which directory and environment variable to use on Window)?
Which source is trustworthy to download this dll? I don't want to download any malware under this dll-name.
Optional: What kind of library is that? What functionalities does it offer?
Additional information
I use CMake as my build tool, CLion as the IDE and MinGW as the compiler.
What I have did so far?
I made sure it still works through the IDE.
I found this dll does not exist in the MinGW installation folder.
I searched the web for more information. Unfortunately, there are only pages unknown to me that only offer the download of this dll. That doesn't satisfy me.
I found the cause of my problem: I had two MingGW installations on my machine. Once the installation that comes with CLion and a separate one. The latter did not have the required dll. However, CLion used its own installation, which in turn owns the DLL. So the solution was to remove the separate installation and include the path to the CLion installation's bin/ directory in the PATH environment variable.
This file is part of MinGW-w64 when using SEH as exception model (as opposed to Dwarf or SJLJ). You need to distribute the .dll files your .exe file(s) depend on in the same folder as the .exe file(s).
If you don't have that file, then you probably have been using libraries compiled with different versions of GCC/MinGW(-w64). I recommend building everything with the same compiler to ensure stable binaries.
Tools like Dependency Walker can help you figure out which .dll files your .exe file depends on.
Or use the command line tool copypedeps -r from https://github.com/brechtsanders/pedeps to copy the .exe files along with it's dependencies.

Netbeans C++ using MinGW and the libnoise library

Using netbeans 7.2 and the most recent version of MinGW (using installer) I can't use the libnoise library. I am properly including the header files, the auto completion confirms this, however the library is simply not working. There is a .lib file and a .dll. I have tried every possible combination of adding them under project > properties > Build > Linker as well as putting the .dll in the base project directory. Despite all this I am still getting undefined reference errors whenever I try and run the code. Does anyone know what to do?
I know that it is possible to link import library files (*.lib) with MinGW, but I still suggest to recompile libnoise.
With the current Makefile, this is not very easy and may break. Thus I've written a CMake script, which doesn't only work on Windows, but should work on all CMake supported platforms. In addition to this, I've cleaned up the directory structure. The code itself hasn't been touched and when you build a library it should essentially be the same as the current one.
libnoise on GitHub
After you've built your shared library, you'll have a libnoise.dll.a and libnoise.dll file. You then add libnoise.dll.a to the linking settings and put the DLL itself next to the binary, or in the working directory.
You have to link the lib file (= adding it to linker libraries) and put the dll to
<project root>/dist/<...>/
(where your exe is put to). There's no need to add the dll to linker too.
Can you please post the error message you get?

Error linking libboost_system in Visual C++

I have a problem using boost.asio. I use Windows XP and Visual Studio 2005
I followed these steps:
I downloaded the latest version (http://sourceforge.net/projects/boost/files/boost/1.46.1/) of W: \boost_1_46_1
I set the environment variable INCLUDE : W:\boost_1_46_1
In the properties of my project (VS->tools->Options project&solutions->vcc++directories) I added $(INCLUDE)
I added in my file. h this:
I get the following error:
LINK : fatal error LNK1104: cannot open file 'libboost_system-vc80-mt-gd-1_46_1.lib
This is a linker error. Find the lib, and go to linker input, and add it there. Be sure to set the libpath as well. This picture should guide you:
The boost::asio library needs to be built. ( Many other boost 'libraries are headers only and do not need to be built ). Building it yourself is a small challenge. Better to use the pre-built binary installer which is here
Once you have the built libraries, one way or another, you have to tell the linker where they are. However, you do not need to specify each individual library by name, just specify the folder that contains them. The easiest way to do this IMHO is to create an environment variable called BOOSTROOT which you you set equal to the folder where you installed boost. Then you tell the linker to look for libraries in $(BOOSTROOT)/lib

Why is VisualStudio looking for this lib file? LNK1104 error

We have a large project using VS2008 and boost 1_42. I'm trying to upgrade to VS2010 and boost 1_44. I installed VS2010 and boost 1_44 and converted the project. Now I am trying to build, and everything compiles, but fails when linking:
LINK : fatal error LNK1104: cannot open file 'libboost_thread-vc90-mt-1_42.lib'
I have changed the include and lib directories to point to the new boost 1_44 files and I have renamed the old boost 1_42 directory.
Why is the linker still looking for a vc90-1_42 file, when it is only using 1_44 headers? Is there a way that I can determine WHY the linker wants this file? The linker obviously thinks it needs the file, but why?
I have cleaned the project and I am re-building to ensure any old build files are erased.
I've run into exactly this problem a couple of times too. It's usually been some old temporary files but like in your case cleaning didn't always do the trick straight away. Does your project include any static libs that might have been built with 1.42?
Something you can try which may or may not be helpful in tracking down your issue:
Rename the old boost directory back to it's original name
Clean the solution
Under C/C++->Command Line->Additional Options add "/showIncludes"
Under Linker->Command Line->Additional Options add "/verbose:lib"
Rebuild all
Then when you build you'll be able to see at which point 1.42 headers are included, etc. in the output window. Somehow doing this helped me in tracking down where the problem was.
Along with changing the lib directory, you need to change the name of the boost library. That's in the Linker | Input section of the project settings.
Your added comment makes it clear that the dependency on the Boost 1.42 library was being created indirectly by another library that hadn't been rebuilt.
For this you basically have two choices: either add that library as a project to your main solution, and make sure it has enough dependency information that it'll be re-built when you upgrade Boost, or use the /Zl compiler switch when you build your library. This tells the compiler you're building a library so you do not want to embed library dependencies like this.
Boost uses
#pragma comment(lib)
command to inform the linker of libraries it needs to link with. It is not an error. If Boost says you need it, it's likely you do.
On How can I find out why the linker wants this file?
There are programs which will go through your app and dlls/libs and report the content of manifests and what the binaries report they depend on. You could then scan the report for the unexpected libraries being included. We used this mainly to find libs including the previous version of the VC runtime.
Have not used the one we had in about 5 years though, now if only I could remember the name of the app!
DependancyWalker (depends.exe) will allow you to see dependancies of dll/exe but not static libs.
You could open each binary as a 'file' in MSVS and look at the manifest content by hand, but I imaging this would be a bit painful. I've not tried this with a static lib.

fatal error LNK1104: cannot open file 'libboost_system-vc90-mt-gd-1_43.lib'

Made a new project, added main.cpp and wrote the code at this URL:
http://www.boost.org/doc/libs/1_43_0/doc/html/boost_asio/example/echo/async_tcp_echo_server.cpp
Also, added the appropriate include path.
What's next?!?!! It seems like a darn mystery to build a boost code!
Been digging on it for more than 10 hours.
Can anyone give a straightforward answer on how to build the boost library from the code under windows, VC9?
You need to use bjam. It is responsible for creating the libraries that your application will use. Once you use bjam, you are going to need to instruct your project to include the lib file. You do this by going into the project's properties -> Configuration Properties -> Linker -> General. Add the directory which created the lib file to Additional Library Directories. You should be capable of correctly linking after that.
I believe that this link describes the steps better than I could attempt in a post
#bogertron: I want to hug you! (:
So, at last, with a real head ache, I've managed to do so.
The exact steps I took, so others will be saved from the head ache:
Went to http://www.boost.org/doc/libs/1_43_0/more/getting_started/windows.html#or-build-binaries-from-source .
Followed the "5.3.1 Get bjam" clause. Downloaded the "pre-built bjam executable for your platform" at this URL: http://sourceforge.net/project/showfiles.php?group_id=7586&package_id=72941 .
Extracted the ZIP file (my platform is Windows).
Ran "build.bat". It produced the file "bin.ntx86/bjam.exe".
Copied this file to my PATH ("...../boost_1_43_0/").
From a command line, executed "bjam.exe" and waited for about 4-5 minutes.
Then got this message at the console: "The Boost C++ Libraries were successfully built!"
That's it, it even tells you where the include & lib files are.
Not all Boost libraries are header only, Boost.System is one of them. The documentation for Boost.Asio tells you that it depends on Boost.System.
With Visual Studio, the Boost libraries use auto-linking, which means you don't have to explicitly link to the libraries you need. You however need to have the necessary libraries in the library search path, either globally or per-project.
If you don't want to build the Boost libraries yourself, you can use the installers provided by boostpro (only up to Boost 1.42 though at the moment). If you want to build them yourself instead, the documentation covers that well.
I had the same error and i followed the SourceForge. The link will take you to a folder of zipped lib and dll files for version of boost.You can download and unzip related library and when copied it to the related location everything gonna be alright ;)
In Visual Studio, right-click on your project, then go to properties and select:
Properties -> Configuration Properties -> Linker
There you add the full path of your library in the tab named "Additional Library Directories".
From the "Boost Getting Started Directions":
"5.2 Or, Simplified Build From Source
If you wish to build from source with Visual C++, you can use a simple build procedure described in this section. Open the command prompt and change your current directory to the Boost root directory. Then, type the following commands:
bootstrap
.\b2"
On Windows, I opened the Visual Studio Command Line from the start menu. First I types "bootstrap" and then I typed ".\b2".
Now with boost_1.50 the Boost.build is included in the zip file: check tools\build\v2\ or better read: ...boost_1_50_0/more/getting_started/windows.html