Using D2XX of FTDI with C - c

I'm trying to use ftd2xx.lib with lcc-win32 compiler but the linker fails. I used CDM v2.12.14 but also previous FTDI driverd give the same errors. I tried to compile on Windows XP and Windows7; same results.
If I link the static library I will get these kind of errors:
File ftd2xx.lib contains unknown section .text$mn.
.text section assumed
File ftd2xx.lib contains unknown section .data$r.
.data section assumed
.data$r: undefined reference to '??_7type_info##6B#'
.text$mn: undefined reference to '__imp__SetupDiGetClassDevsA#16'
.text$mn: undefined reference to '__imp__SetupDiEnumDeviceInterfaces#20'
If I link the dynamic ftd2xx.lib (with ftd2xx.dll placed in the same dir of .exe file) I will get this:
Error e:\c\ftdi_cnt\main.c 11 undefined reference to __imp__FT_Open
(Note that main.c used for this test contains just a single FT_Open() call).
Is there anyone that was able to run ftd2xx.lib with lcc-win32 compiler or that is currently using lcc-win32 and can make a quick test? Here is the latest FTDI driver. Thank you.

Finally it works!
Here is what I did:
1) Ian suggested I should use "Utils --> Import foreign library"; as a matter of fact this is the same of running from the command line:
pedump /EXP ftd2xx.lib >ftd2xx.exp
buildlib ftd2xx.exp ftd2xxy.lib
I've already tried that using for ftd2xx.lib the dynamic .lib but without success.
2) I ran pedump again, this time using the static .lib and I got a warning message about unknown dll name, so I edited the first line of ftd2xx.exp adding that name (ftd2xx.dll).
3) I defined FTD2XX_STATIC before including ftd2xx.h
4) I linked the new library ftd2xxy.lib
Note that you can't use "Utils --> Import foreign library" because you need to modify ftd2xx.exp before re-building the library.
I hope this could be helpful for others.

Related

Go compile returns duplicate symbols for architecture x86_64 error when I import 2 different packages which use C package via Cgo

Here is my code:
package main
import (
kusb "github.com/karalabe/usb"
tusb "github.com/trezor/trezord-go/usb"
)
func main() {
kusb.Enumerate(0, 0)
tusb.InitHIDAPI(nil)
}
When I compile (I'm using go mod to manage the packages), it returns this error:
duplicate symbol _libusb_dev_mem_alloc in:
/var/folders/fm/1rln65d94mn45s0h5l78tdyh0000gp/T/go-link-624554542/000002.o
/var/folders/fm/1rln65d94mn45s0h5l78tdyh0000gp/T/go-link-624554542/000020.o
ld: 136 duplicate symbols for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Why?
Some investigation i had:
The both packages use the same hidapi and libusb C packages in order to interact with usb devices.
Those C packages are identical, hence it defines the same functions so i think it is directly related to the error.
in trezord-go/usb, they include .C file, not the header file.
It is very counterintuitive to me because in the perspective of package users, I shouldn't need to worry about how a C package is used in the internal of the package, only the exposed types, functions and its behaviors.
Can anyone really explain what is going on here and how can I import both of them? They do different functions, eventhough they use the same C package.
From here: https://www.repustate.com/blog/go-duplicate-symbols-for-architecture-x86_64/
"What does this mean? Well, it means we're trying to link the same symbol name (in our case, a method) from two (or more) different source files. The fix was easy: rename one of the methods by updating the header file, the source file (.c or .cpp file) and lastly, updating your references to the symbol in your Go code, if it is directly referenced there."
Will it help ?
I was running into the same issue for hours and finally found the fix on a google groups channel
A package you import could be using cgo, you don't have to be using it directly
...
You can try CGO_ENABLED=0 go build and if it works then it is cgo related.
This was the charm that i was looking for! Hope this works for you too.

Error: L6218E: Undefined symbol main (referred from __rtentry2.o)

anyone can help me?? my board is LPC1768 and the sensor is BMP180
Rebuild target 'Target 1'
compiling BMP180.c...
compiling I2C.c...
assembling startup_LPC17xx.s...
compiling system_LPC17xx.c...
compiling GPIO_LPC17xx.c...
compiling PIN_LPC17xx.c...
linking...
.\Objects\asdsa.axf: Error: L6218E: Undefined symbol main (referred from __rtentry2.o).
Not enough information to list image symbols.
Finished: 1 information, 0 warning and 1 error messages.
".\Objects\asdsa.axf" - 1 Error(s), 0 Warning(s).
Target not created.
I found the solution is easy, but before going deeper into the solution, keep in mind that C compilation unit (C Compiler and Assembler at least) compiles each pure C source file after resolving necessary pre-processor directives, and generates a relocatable object file as a result of compilation.
After the compilation unit does its job, there is another unit that is responsible for combining individually every source file that is compiled successfully into the relocatable form of one big object file for all. This unit is called Linker and the operation is called Linking
A very important feature in relocatable object file is that what is called variable, function will be noted as symbol so far. The linker has to solve the symbols, defining what is originally defined in an object file, reference what is being used in another to their original object file.
After this motivation, now we can call main() function as main() symbol.
I Found that the problem is because the source file that contains the main() function was not compiled. As a result, there is no a relocatable object file that contains the symbol corresponding to main() function. Hence, the compiler is complaining: you asked me to use (reference) a symbol you guaranteed to be found (defined) in another file but I found no such symbol!
The solution:
For Kiel IDE, to queue a source file for a compilation; you gotta shortlist it in the category "Source Group",by clicking right, either adding new files to group, or existing files to group. It will result in something like the following figure:
Now we have a main function, is turned (defined) to main symbol later, and found by the linker to reference it to whatever use it in any other relocatable object files.
I solved this problem with the following steps;
Delete your old project and create new project
Choose true library from Manage Run Time Environment like so:
Configure "Options for Target" segment. Define symbol USE_STDPERIPH_DRIVER and define project path like so:
Test your configuration. Please write the following code:
#include "stm32f10x.h" // Device header
int main() {
}
I had the same issue. The problem was that the function name in .c file had a different name with the one in the .h file, and I didn't know.
just add your c file (ex: 'main.c') to the source group (ex: 'source group 1') by expanding the target then right click on the source group, choose add existing files to group 'your source group', then choose the main.c file.
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/14222.html
This should help.
Just create a dummy main() or main.c file. Linker can't find it in your pjt.
For solution only add this file C to driver folder and translate it,
Solved: This "Target Not Created" Issue was Resolved by the setting of Run Time Environment as shown in below(url) image.https://i.stack.imgur.com/kJ4IL.jpg ( consisting of CMSIS and Device supporting components in Run time environment)
{ compiling TransformFunctions.c...
linking...
Program Size: Code=768 RO-data=320 RW-data=4 ZI-data=612
FromELF: creating hex file...
".\Objects\LPC1768_B_T.axf" - 0 Error(s), 0 Warning(s).
Build Time Elapsed: 00:00:07
}

Why do I need to manually link the C runtime library when creating an EXE out of static libraries without any object files?

I'm pretty new to working with libraries and I'm in the process of trying to understand some specifics regarding static libraries and object files.
Summary
The behavior I'm noticing is that I can link several objects to make an executable with no problem, but if I take an intermediate step of combining those objects into static libraries, I cannot link those static libraries to make an executable without additionally specifying the needed C Run-time library in the link command.
Also, or the record, I'm doing the compiling/linking with Visual Studio 2010 from the command line. More details of the process I'm following are below.
First, let's say I have four source files in a project: main.c, util1.c, util2.c, and util3.c.
What works
I can compile these sources with the following command:cl -c main.c util1.c util2.c util3.cAs a result, I now have four object files: main.obj, util1.obj, util2.obj, and util3.obj. These object files each contain a DEFAULTLIB statement intended to inform the linker that it should additionally check the static C Run-time library libcmt.lib for any unresolved external dependencies in these object files when linking them.
I can create an executable named "app_objs.exe" by linking these objects with the following command:
link -out:app_objs.exe main.obj util1.obj util2.obj util3.obj
As mentioned in step 1, the linker used the runtime library due to the compiler's step of adding a default library statement to the objects.
Where I'm confused
Let's say I want to have an intermediate step of combining these objects into static libraries, and then linking those resulting LIB files to create my executable. First, I can create these libraries with the following commands:
link -lib -out:main.lib main.obj
link -lib -out:util.lib util1.obj util2.obj util3.obj
Now, my original thought was that I could simply link these libraries and have the same executable that I created in step 2 of "What works". I tried the following command and received linker error LNK1561, which states that an entry point needs to be specified:
link -out:app_libs.exe main.lib util.lib
From Microsoft's documentation, it is evident that linking libraries without any object files may require entry points to be specified, so I modified the command to set the subsystem as "console" to specify that the executable in intended to be a console application (which seems to imply certain entry points, thereby resolving that error):link -out:app_libs.exe -subsystem:console main.lib util.libUnfortunately, now I get a linker error stating that mainCRTStartup is an unresolved external symbol. I understand that this is defined in the C runtime library, so I can resolve this issue by manually specifying that I want to link against libcmt.lib, and this gives me a functioning executable:link -out:app_libs.exe -subsystem:console main.lib util.lib libcmt.lib
What I'm not understanding is why the default library info that the compiler placed in each object file couldn't be used to resolve the dependency on libcmt.lib. If I can link object files without explicitly stating I want libcmt.lib, and I created static libraries that are containers for the object files, why can't I link those static libraries without having to explicitly state that I want libcmt.lib? Is this just the way things are, or is there some way I could create the static libraries so that the linker will know to check for unresolved symbols in the runtime library?
Thanks for your help. If I have some fundamentally incorrect ideas here, I'd love suggestions on good references to learn all of this correctly.
Well the answer to your misunderstanding is that .lib files are often a product in themselves, and the compiler can't make those assumptions safely. That's what "external" is for.
If I produce binaries for someone's platform because its users are totally helpless, and they want/need static linkage, I have to give them foo.h and libfoo.lib without tying them to a specific runtime entry point. They may very well have defined their own entry point already for their final product, whether DLL or EXE.
You either want the runtime, or you want your own .obj that contains your entry point. Be warned that declaring and defining mainCRTStartup on your own may mean you're not executing important instructions for the target platform.

Do I need an "so" file or what's wrong?

(I'm on Windows.)
I try to build pysox. Therefore I built libsox (part of SoX). It is said, that pysox needs "libsox.so and libsox.a in your link path." When building libsox I got "libsox.a", "libsox-1.dll", "libsox.dll.a", "libsox.la", "libsox.lai" and many other strange files. When I placed "libsox.a" in my link path, the previously shown error disappeared. But now the build script has an error when it calls mingw32-gcc which says:
C:\Programme\MinGW\bin\mingw32-gcc.exe -shared -s build\temp.win32-2.7\Release\pysox\sox.o build\temp.win32-2.7\Release\pysox\sox.def -LC:\Programme\Python\libs -LC:\Programme\Python\PCbuild -lsox -lpython27 -lmsvcr90 -o build\lib.win32-2.7\pysox\sox.pyd
build\temp.win32-2.7\Release\pysox\sox.o:sox.c:(.text+0x3a96): undefined reference to `sox_get_encodings_info'
build\temp.win32-2.7\Release\pysox\sox.o:sox.c:(.text+0x5035): undefined reference to `sox_get_encodings_info'
build\temp.win32-2.7\Release\pysox\sox.o:sox.c:(.text+0x795d): undefined reference to `bcopy'
build\temp.win32-2.7\Release\pysox\sox.o:sox.c:(.text+0xa8b3): undefined reference to `bcopy'
collect2: ld returned 1 exit status
error: command 'mingw32-gcc' failed with exit status 1
The following attempts didn't work:
Placing "libsox-1.dll" in link path
Renaming it to "libsox.dll"
Renaming it to "libsox.so"
Placing all files generated along with "libsox.a" in link path
Do I really need an "so" file on Windows (how do I get it)? Or what has to be changed?
MinGW uses a static interface library for each dynamic link library (DLL). The libsox.dll.a library is the one you need at link time, i.e. that needs to be copied into the link path. libsox-1.dll is required in the PATH at runtime, but not needed at link time.
You don't need a .so file on Windows platforms. It seems that some symbols are missing from the static library libsox.a, or that a library is missing from the link line. Windows platforms do not allow unresolved symbols in DLLs, contrary to UNIX-like .so platforms. You might have to give the library containing sox_get_encodings_info and friends explicitly on the command line, remembering precedence on the linker line.

How to use C static libraries in D?

I'm completely stumped on how to get FreeType 2.4.8 compiled as a static lib and usable from within my D application in Windows. I've tried running it over with objconv, coff2omf, and trying extern(C)/extern(System), etc. but nothing seems to work. I'm getting symbol not found errors, access violations and just a bunch of unhelpful errors.
How can I work around this? Am I correct in using pragma lib to link to my static libraries, and how do I reliably convert COFF static libs to OMF which DMD/Optlink can use?
EDIT: Some examples of what I've tried doing:
Compiling the FreeType source with VS 2010 as a static lib, linking in my D code with pragma lib. (Returned a "library format unknown" type error)
Same as above, but converting to OMF format using objconv and then trying to link with pragma lib. (Linked successfully, but still not able to call functions.)
Compiled a DLL of the FreeType source, ran it through implib to create an import library, tried linking with pragma lib. (Linked successfully, but unable to to call any functions due to "attempt to privileged function" or "access violation" errors)
I've tried defining function prototypes as all of: extern(System), extern(C), and extern(Windows). The first and third mangle the functions names of the extern-ed functions such that they don't match the static libraries, and the second compiles, but I get access violations during runtime when I actually try and call the functions.
I'm able to get it working via dynamic libraries and symbol loading, but I'd much prefer to not require a bunch of external dependencies when deploying my project.
I'm pretty sure Derelict2 has FreeType bindings: http://www.dsource.org/projects/derelict (See DerelictFT).
Yes, you will need extern(System) in your .d files with FT function declarations.
Static library a collection of object files. So no need for any kind of conversion (omf2coff, etc). DMD accepts a static libraries as arguments, so simple dmd file1.d file2.d C:/path/to/freetype.lib should work.
Edit:
I was wrong. Apparently I needed to read some documentation about the COFF2OMF.
Quote: The Microsoft COFF format apparently changed with Visual C++ 6.0. To use coff2omf on a .lib file with the newer format, use Microsoft's linker to convert the file to the earlier COFF format:
link /lib /convert freetype.lib
So, judging by the statement above you need to perform 2 steps.
First use the Microsoft's linker to convert static library you made with the VisualStudio (in COFF format) to the old COFF format as described above.
Now execute coff2omf freetype.lib to convert the static library into the OMF format.
It should now be ready to be used with the DMD the way described originally in my post.

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