I have set up MinGW and Eclipse with CDT for C++ developing on Windows. Everything works great until I #include <windows.h>. As soon as I do that, I get the linker error message c:/mingw/bin/../lib/gcc/mingw32/4.6.2/../../../../mingw32/bin/ld.exe: final link failed: Invalid argument whereby the path at the beginning resolves to C:/MinGW/mingw32/bin/ld.exe.
I have no idea what the error message tries to tell me... so please help me to decrypt it.
Since I actually don't agree to Lol4t0's opinion that this is too localized here is the ugly answer: Reinstalling G++ solved the problem.
I think the problem also could have been that I maybe forgot to install one of the parts listed here (where I got it from) for the first time... but now I recognize the link is completely deprecated (2005). So one should use another anyway.
Perhaps you are missing one of the linking parameters on the command line.
E.g., you might want to add the -lgdi32 -lkernel32 -luser32 if you use any of WinAPI functions declared in <windows.h>
Since you are getting errors in Eclipse, add these libraries (gdi32, kernel32, user32) here:
Project Proprerties -> C/C++ build -> Settings -> GCC Linker -> Libraries -> "add the library"
(this is taken from eclipse cdt command line input)
Related
Context: I'm using Qt 5.9.3 on Windows, building for MinGW 32-bit. The Qt part is a side issue though - the problem seems to be with MinGW. The version of MinGW is 4.3.0, supplied prebuilt as part of the Qt installation.
I'm building a library which talks to a USB device over HID. Everything compiles fine, but it fails at the link stage with
./..\..\object\debug\usb_hid_device.o: In function `ZN8MyApp3USB5Win3213getDevicePathB5cxx11Ell':
<MYPATH>/../../source/win32/usb_hid_device.cpp:99: undefined reference to `HidD_GetAttributes(void*, _HIDD_ATTRIBUTES*)#8'
./..\..\object\debug\usb_hid_device.o: In function `ZN8MyApp3USB5Win3214CHIDDeviceImplC2EllRNS_15LogPerComponentE':
<MYPATH>/../../source/win32/usb_hid_device.cpp:200: undefined reference to `HidD_FlushQueue(void*)#4'
The linker command is
g++ -shared -mthreads -Wl,-subsystem,windows -Wl,--out-implib,<MYPATH>\bin\debug\libusb_hid_comms.a -o <MYPATH>\bin\debug\usb_hid_comms.dll object_script.usb_hid_comms.Debug -lhid -lsetupapi -LC:\Qt\Qt5.9.3\5.9.3\mingw53_32\lib C:\Qt\Qt5.9.3\5.9.3\mingw53_32\lib\libQt5Guid.a C:\Qt\Qt5.9.3\5.9.3\mingw53_32\lib\libQt5Cored.a
If I omit -lhid I get the same errors. I also get the same errors if I remove -lhid and explicitly set the path and filename to libhid.a. If I deliberately mistype the path and filename, it comes up with an error, so I know the command-line is getting parsed correctly. But for whatever reason, MinGW appears to not be linking with one of its own library files.
I've also tried removing -lsetupapi and I get the linker errors I'd expect for the functions defined in there. Likewise the Qt library files. But it seems that specifically for libhid.a, MinGW can see the library file but just isn't going to link with it.
Has anyone else seen this? Or can anyone else with the same (or similar) version of MinGW confirm or deny that they can link with libhid.a? Or is there something obviously wrong with what I'm doing?
I've just found the answer. I'm posting an answer myself so that other people know in future, because I think this is still a valid question which people might want to know about.
The problem is the include file hidsdi.h. The majority of other header files which pull in Win32 API calls have extern "C" around the function declarations. However this one doesn't! The result is that we end up with C++ name mangling for linker symbols, instead of the C-style "_" in front of the linker symbols.
The solution is to use
extern "C"
{
#include <hidsdi.h>
}
and then everything works fine.
The version of hidsdi.h with the older version of MinGW (which I'm porting from) did have that protection around the function declarations. However it looks like it's gone in the newer version.
I am trying to work through this tutorial on OpenCL, on a Windows 10 dev system which has integrated Intel HD graphics. I have installed Intel's OpenCL SDK. I have added the include directory from the SDK install into Properties > C/C++ General > Paths and Symbols > Includes. I am using MinGW as my compiler for Eclipse
In response to a number of linker errors that popped up when I first tried to compile the project, I set up the linker in eclipse to point to opencl.lib as outlined in this answer.
That took care of the linker errors, but there's an offending line from the tutorial which makes it impossible for the tutorial boiler-plate to compile:
87 cl_int result = program.build({ device }, "");
Set up as I am, this gives me the following warning and error:
..\src\main.cpp:93:32: warning: extended initializer lists only available with -std=c++11 or -std=gnu++11
..\src\main.cpp:93:45: error: no matching function for call to 'cl::Program::build(<brace-enclosed initializer list>, const char [1])'
If I'm reading this correctly (I haven't used C++ since before C++11 was a thing), the compiler is first warning me that it doesn't properly recognize what {device} is supposed to be (a vector of devices which has only one entry in it, initialized earlier in the code). Then, since it doesn't recognize {device}, the compiler errors out because it can't find a signature for cl::Program::build with arguments that match whatever-the-heck it's interpreting {device} to be.
Following the warning's advice, I followed the instructions given in this answer to add the -std=c++11 option for the compiler. However, when I do that the linker errors come back. Trying to compile with these options results in about thirty errors which all basically say they can't find any reference for the CL calls in the library files. For example:
C:/Program Files (x86)/Intel/OpenCL SDK/6.3/include/CL/cl.hpp:1753: undefined reference to `clGetPlatformInfo#20'
How do I make the compiler behave? I think I remember reading somewhere that the order of compiler options in the command line matters withe regards to linking, could that be messing up my compile since I added the -std=c++11 option?
I (sort of) figured out why the compiler was unhappy--the library I was linking was the x64 library for OpenCL installed in [base Intel dir]\OpenCL SDK\6.3\lib\x64, but (I think?) my compiler is not set up to create x64 apps. When I link to the .lib file in OpenCL SDK\6.3\lib\x86 my linker errors disappeared.
I am trying to use Eclipse CDT with the Cygwin GCC toolchain in order to read in some images using png++. I have installed the png++ headers (I tried both 0.2.5 and 0.2.7) in my Cygwin, and it compiles fine using the external builder settings with make, but for some reason the editor underlines "image" from png::image in the very simple code:
#include <png++/png.hpp>
int main( int argc, char* argv[]){
png::image<png::gray_pixel> t(128,128);
return 1;
}
And gives the error:
Invalid template arguments.
I looked around a bit for this error, and it seems for other people it was caused by not having GCC set to use C++11 (such as Invalid template arguments on map std::map< std::string, Stock*> &stocks), but I do not think that is an issue with me, since I have my "CDT GCC Built-in Compiler Settings Cygwin" provider command set to:
${COMMAND} ${FLAGS} -E -P -v -dD -std=c++11 "${INPUTS}"
And the line std::normal_distribution<double> distribution(5.0,2.0); does not give an error.
I can remove the error underline by turning off "Invalid template argument" under the project properties -> C/C++ General -> Code Analysis, but the problem is deeper than that, as none of the auto-completes will work for the object of type png::image, and if I try and use it in a function, for example:
void pngTest(png::image<png::gray_pixel> im, int other) {}
it gives the error: Invalid arguments ' Candidates are: void pngTest(?, int) '
So it seems it does not resolve the type at all. What might be causing this?
Turns out this was not actually a bug with Eclipse parsing, but an incompatibility with Cygwin style symlinks. In png++'s png.hpp and types.hpp it includes png.h from libpng, but in Cygwin png.h (in /usr/include) is a Cygwin style symlink to the current libpng (in my case the file contained the text: !<symlink>libpng16/png.h).
So Eclipse could not resolve this include, even though Cygwin's GCC could, and it was making the typedefs in types.hpp not resolve correctly. This is why I was getting an invalid template arguments error in eclipse, png::gray_pixel was not a valid type. I noticed this when I put <int> instead and it no longer gave an error. So that was the problem.
I changed the include paths from png.h to libpng16/png.h in both png.hpp and types.hpp
and now everything in eclipse is resolving correctly after a right click on the project -> index -> rebuild. Alternatively you could symlink png.h, pngconf.h, and pnglibconf.h in /usr/include to the appropriate libpng subfolder using the windows mklink command and remove the Cygwin style symlinks.
If anyone knows a way for Eclipse to work seamlessly with Cygwin symlinks then post here and I will accept that as the answer, since obviously that is a little better than this hacky fix.
Thank you guys for the comments, but it seems thankfully that this time it was not an Eclipse issue.
I've been having some difficulty compiling a piece of C++ code for the physics engine Bullet Physics, and was hoping to get some advice.
This is my first time using gcc as a compiler, and including directories for compiling in general, so I'm going to give my whole process of problem-solving because I'm not sure where I went wrong or what the pertinent information is.
When I first tried to compile the code I got a fatal error about "No such error or directory", so I decided to add the directory with the -I option (1). It fixed the first error, but another popped up. Again, I was able to make the error go away with a -I option to the directory needed(2).
Then I got a whole long list of errors like the following:
main.cpp:(.text+0x33): undefined reference to 'RagdollDemo::initPhysics()'
main.cpp:(.text+0x84): undefined reference to 'glutmain(int, char**, int, int, char const*, DemoApplication*)'
/tmp/cc4MqhHm.o: In function '__static_initialization_and_destruction_0(int, int)':
main.cpp:(.text+0xe7): undefined reference to `std::ios_base::Init::Init()'
I tried a few different things, but the solution ended up using my home bullet folder (or usr/local/include/bullet/) with the --sysroot option (3).
This created a lot of errors for the C++ header files, and then I linked to a few more directories with -I (4-5), but at after one of the added directories the same set of errors that I thought I solved with the --sysroot addition popped up again (6).
I can't tell what to do now. I would guess that declaring the bullet folder as my root makes it impossible for the compiler to find the required C++ files in my actual root directories, but I don't what to do about that... and when I tried including the C++ files I needed, the compiler seemingly forgot I told it to use bullet as my root.
Final compilation I tried before I gave up and realized asking for help might be better than spending 3 hours looking at documentation without any idea of what the exact problem is. Numbers correspond to the steps above.
gcc
(3)--sysroot=/home/josh/bullet-2.82-r2704/
(1)-isystem/home/josh/bullet-2.82-r2704/Demos/OpenGL/
(2)-isystem/home/josh/bullet-2.82-r2704/src/
(4)-I/usr/include/
(5)-I/usr/include/c++/4.8
(6)-I/usr/include/x86_64-linux-gnu/c++/4.8/
./main.cpp
I'm using Ubuntu 14.04 LTS and my OS and emacs 24.3.1 as my IDE.
Any help would be greatly appreciated.
Best,
Josh
What you are seeing is not include issue. Linker is failing to link with symbols. You need to link with proper library, for example lglut
How can my program compile successfully but eclipse shows me "Semantic Errors" and how could I get rid of those errors?
The error messages I have are the following
Method 'c_str' could not be resolved (this happens also for compare and size on strings)
Here an example:
std::string someotherstring = "test";
std::string name = someotherstring.c_str();
The problem here is that it also creates follow up errors which seem all to be not true, my software compiles and runs as intended and even uses the "c_str()" returns to process messages. It seems only to be a display issue in Eclipse.
I have searched now for hours, tried to use a custom indexer but for some reason it won't go away. Maybe someone else has a good idea what to do here as Google spits out nothing about this specific problem. (I have even tried to use different C++11 standard flags as I thought it might had an impact)
I had the same problem. Solved by simply run a index -> rebuild. You can find that by clicking on the project main folder with the right button.
Cheers
If you're building your projects using mingw and using C++11, you can not use the default dialect option of -std=c++0x.
Click on 'GCC C++ Compiler' and in the Command: textbox, enter -std=gnu++0x after the g++