How to delete debug symbols in static libs - linker

I have four libraries that I wrote in C. Now I want to share these libraries (static libs for example, libA.a) with a software developer who will use them to generate a "final" executable.
My question is, how can I delete the debug symbols so that he doesn't find some information about the working process inside my libs?
Thanks in advance.
Development Environment: GreenHills
Compiler: ccarm

Related

How to specify static linking for standard libraries in yocto-cmake?

I am new to cmake so, sorry if this question is very basic.
I want to build my project as statically linked with each standard library it uses.
Like, in gcc if we want to link the standard system libraries(libc, libgcc etc) as static, we specify '-static' option at the time of compilation.(Like gcc main.c -static -o main).
How we can achieve the same in cmake?
I have read multiple threads to define a how to define a library, how to build, link(as static & shared). But that is all for a custom library, I need information for standard system libraries.
[Edit]
In my project, I am using yocto at the top and the cmake is been used underneath it. running directly cmake works fine, as the generated executable has no dependencies on any shared library, all the used libraries are linked statically. But compiling from yocto causing the issue. the executable generated from the yocto build shows the dependencies on several standard shared libraries.
How we can specify static linking of standard libraries in yocto cmake?
Thanks in advance.

Having Difficulty Integrating JSON Library with My AVR Microcontroller Code

I am a relatively inexperienced C developer with no previous experience in integrating libraries made by other developers into existing projects.
Basically, I need a means of parsing JSON data in an AVR microcontroller for a university project. To this end I attempted to download and integrate jansson (https://github.com/akheron/jansson) into my existing build of the microcontroller code. I am working with Atmel Studio in Windows 10, but I have also installed Code::Blocks with MinGW GCC (on the same Windows 10 installation) for the purpose of building the library, and to attempt to integrate the library into a native Windows application. So far, neither has been successful, and I get the same errors. All of the online resources I've found so far have been to basic to be useful, or well beyond my comprehension.
This is what I have done thus far:
I began by attempting to build the software and then integrate it into an existing project per the instructions in https://jansson.readthedocs.io/en/2.11/gettingstarted.html. I installed CMake, built the project files for Code::Blocks with cmake.exe -G “CodeBlocks - MinGW Makefiles”, then opened the project and built everything. A few of the targets (I believe related to testing) failed to build, but jansson itself built and output libjansson.a to the \lib\ directory, so I didn’t think too much of it.
That is as far as I’ve been able to get. In both Atmel Studio and Code::Blocks, I do the same thing: add jansson.h to the relevant include paths, add #include “jansson.h” to all of the relevant files, and add libjansson.a as a library in each IDE’s respective linker options. I’ve tried various things like adding and removing flags to the linker, but the output is always “cannot find -ljansson”, “undefined reference to ‘json_object_seed’” (which is a function in the API I’m calling for no reason other than to see if the project has built properly) and/or “ld returned 1 exit status”.
I cannot help but feel as if the issue is with the line “cc -o prog prog.c -ljansson” in the documentation linked above. I really just don’t understand how to set up the linker properly to get the project to build.
If anyone could give some insight into what I’m doing wrong/the correct way to link this library I would appreciate it a lot.
The library itself should be built with appropriate toolchain. I assume that you built your library twice, one version using MinGW toolchain and other with avr-gcc toolchain.
If you compile target application and linker cannot find library, then try to add path of directory that contains *.a file of library to linker settings (linker search path). Let's say you have: /path/to/lib/libjansson.a
In Code::Blocks: Project → Build options → Search directories → Linker add /path/to/lib/. Then it should link with include path set, for example: cc -o prog prog.c -ljansson -L/path/to/lib/
In Atmel Studio when you add a library in Solution Explorer → Libraries → Add Library it should automatically add library search path to linker options. If you check Project → Properties → AVR/GNU Linker there should be (between other options): -Wl,-ljansson -Wl,-L"/path/to/lib/"
If you copied library files (libjansson.a and jansson.h) to your application's project directory, it will be convenient to use relative paths to library files.

Statically linking libvips to a Rust program in Windows

There is a lib-sys for libvips on crates.io, however it uses pkg-config which searches the system for the library to link to dynamically, not statically.
I want to provide libvips with the final binary of my software in .dll or .exe along with it since the user should only install one executable with everything in it, C and Rust code.
Looking at the Rust book's FFI linking section, we can link lib.a files easily, but libvips is a huge complex C library that has releases for Windows in .dll and .exe format. I do not know how to link these Windows binaries of libvips to a Rust program statically.
Potentially, I could build it from source manually and link it manually, but the build process seems very complex and it uses scripts and Docker. I would have to replace those scripts with a build.rs of my own that did the same but that seems very hard to me since I'm a beginner at this. I know I would have to set rustc-link-search in build.rs, but I don't know how to compile the .a files for libvips. Rust book on this
My goal is to FFI into libvips from Rust. I am using Windows 10 and want to cargo build the project and have the Rust code and libvips in one distributable binary with no other dependencies.
edit-1:
the vips-dev-w64-web-x.y.z.zip contains libvips.lib , libvips.dll.a files, pkgconfig .pc files, as well as the normal .dll and vips.exe. Can i use these .lib and .a files and if so exactly how? Will it link statically? Are these .pc files useful for my situation?
Just ship the libvips bin area in your tree somewhere, add it to PATH on startup, and link dynamically. This is how electron apps and node.js packages that use libvips work. Static linking for complex libraries died a while ago, it's not worth trying.
As much as anything, it would be a potential licence violation. libvips is LGPL, so you MUST link dynamically (or include enough of your code to allow relinking), or your whole application becomes open source.

Problems with linking lua statically

I'm trying to link lua statically into my C++ application with VS2012. I downloaded the vs11_lib files off of sourceforge and added linker dependencies for this file, lua52.lib. I'm now getting all sorts of link errors when I try to compile and I'm pretty sure I missed a step. Again, I'm doing this statically since I'd like my application to run stand-alone. Any pointers would be greatly appreciated!
The best way is to build embeddable Lua yourself. Download source files for your desired version, create a static library project in VS2012, copy the source files (*.h and *.c to the VS project, not VS solution) and add all source files to the project, except luac.c and lua.c, which are needed for standalone executable rather than embedded library (and they conflict with each other in one project anyway).
After that compile the release version and you got yourself lua5.x.lib that you can link against. If it's still not working, then the problem might be that you added linker dependencies in the wrong place.
Lua sources can be compiled as C or C++. I figure the lib files you are trying to use are compiled as C and you are including their headers as C++. The outcome would be that the names of the functions are different; ergo, the linking errors.
If you are using a C lib in a C++ file, wrap the lib's header like so:
extern "C" {
#include "lua.h"
#include "lualib.h"
#include "lauxlib.h"
}
For more detailed instructions using Lua with Visual Studio, see this article.
UPDATE:
As, #lhf says in a comment, the newer distributions of Lua provide a C++ header lua.hpp which does the same thing. It is described for older distributions in PIL.

Gwan include scripts

I am currently trying to import some libraries into my Gwan C script. I have read through the manual and am using #pragma include to include the folder that my libraries are in, and then use #pragma link to actually include the libraries, but when I run the script it error and says /usr/bin/ld: cannot find -lxxxx.a
Heres current code
#pragma include "/opt/Gwan/libraries/xxx"
#pragma link "xxxx.a"
current Gwan version 4.3.11. Thanks, any help will be appreciated
[EDIT]
All is working fine now, changed all my libraries to shared and placed them in /usr/lib
While you can link object code and static libraries with G-WAN scripts, you should rather use a dynamic library because it will only be loaded once in memory.
Do you succeed in running the (many) G-WAN examples that use third-party libraries?
(libsqlite, libcairo, libmySQL, libcURL, liboauth, libmemchached, ImageMagick, etc.)
Don't forget that you must indicate the library file name without the starting "lib" prefix (ie: sqlite3 for libsqlite3.so).
Also, libraries compiled for 64-bit won't work with G-WAN 32-bit (and vice-versa).
If this can help, there's a G-WAN FAQ dedicated on libraries which gives tips and tools to check for possible problems.
Maybe you should give the whole library names instead of the xxx in your example.

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