When I used the x264 DLL in another project, the "undefined reference error" is reported when making that project!
This is my (example_exe.cpp) code:
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#define X264_API_IMPORTS
#include "x264.h"
int main(void)
{
x264_param_t *t;
x264_encoder_open(t);
return 0;
}
and This is how I compile and make my code:
g++ -c example_exe.cpp
g++ -o example_exe.exe example_exe.o -L. -llibx264-142
and I got the following error:
example_exe.o:example_exe.cpp:(.text+0x22): undefined reference to `x264_encoder_open_142(x264_param_t*)`
As you compile C++ (and not C) than you need to use extern "C" {...} for x264.h header i.e.
extern "C" {
#include "x264.h"
}
Related
This question already has answers here:
C++ Global variable declaration
(5 answers)
Closed 9 months ago.
I am working on a project on Arduino ESP32 and I have a lot of Global variables (for data generation). I have decided to create a library in order to orgenise my work a little better. But I use this library into other librari's that I had to create for other usage. after compilation it I have the following error :
sketch\OX2inj_LEVEL_OX2.cpp.o:(.data.addrChipId+0x0): multiple definition of `addrChipId'
sketch\First_Useage.cpp.o:(.data.addrChipId+0x0): first defined here
sketch\OX2inj_LEVEL_OX2.cpp.o:(.bss.ChipID+0x0): multiple definition of `ChipID'
sketch\First_Useage.cpp.o:(.bss.ChipID+0x0): first defined here
here is my .ino (main) code :
#include <Arduino.h>
#include "Var_Str_EEPROM.h"
#include "Def_Global_Var.h"
#include "First_Useage.h"
//---------somthing
void setup()
{
Serial.begin(115200);
//---------somthing
Serial.println(ChipID.ReadStrEEPROM());
//---------somthing
}
void loop()
{
//---------somthing
}
here is my "Def_Global_Var.h" code
#ifndef Def_Global_Var_H
#define Def_Global_Var_H
#include "Var_Str_EEPROM.h"
uint16_t addrChipId = 1;
VarStrEEPROM ChipID(addrChipId);
#endif
here is my "First_Useage.h" code
#ifndef First_Usage_H
#define First_Usage_H
void getchipid();
#endif
here is my "First_Useage.cpp" code :
#include "First_Useage.h"
#include <Arduino.h>
#include "Var_Str_EEPROM.h"
#include "Def_Global_Var.h"
void getchipid()
{
uint32_t chipId = 0;
for(int i=0; i<17; i=i+8)
chipId |= ((ESP.getEfuseMac() >> (40 - i)) & 0xff) << i;
ChipID.WriteStrEEPROM(String(chipId));
}
My understanding is that, when I use the #include "Def_Global_Var.h", the programme thinks that : "I am calling the library" and it sees that it has been called before and it does not like it.
Is it somehow correct ? and if it is(or not) correct what should I do?
EDIT : sorry I have put the wrong part of the prog. it has been corrected now
The actual cause is that the header is included into several source files, so you end up with multiple conflicting definitions of these variables in your .o files.
You shouldn't normally define global variables in header files at all; you should only declare them as extern:
#ifndef Def_Global_Var_H
#define Def_Global_Var_H
...
extern uint16_t addrChipId;
...
#endif
The second step is to define the variable in the corresponding .cpp file, this time without the extern keyword:
// Def_Global_Var.cpp
uint16_t addrChipId = 1;
Since Def_Global_Var.o gets linked only once, there should be no more conflicts.
Having issues with GetObject. Intellisense in Visual Studio keeps evaluating the method as GetObjectW
...
unresolved external symbol "__declspec(dllimport) public: virtual class Aws::Utils::Outcome<class Aws::S3::Model::GetObjectResult,class Aws::Client::AWSError > __cdecl Aws::S3::S3Client::GetObjectW(class Aws::S3::Model::GetObjectRequest const &)const " (_imp?GetObjectW#S3Client#S3#Aws##UEBA?AV?$Outcome#VGetObjectResult#Model#S3#Aws##V?$AWSError#W4S3Errors#S3#Aws###Client#4##Utils#3#AEBVGetObjectRequest#Model#23##Z)
Here are my includes
#include <aws/core/Aws.h>
#include <aws/core/auth/AWSCredentialsProvider.h>
#include <aws/s3/S3Client.h>
#include <aws/s3/model/PutObjectRequest.h>
#include <aws/s3/model/GetObjectRequest.h>
#include <aws/s3/model/DeleteObjectRequest.h>
#include <aws/s3/model/GetBucketLocationRequest.h>
#include <aws/s3/model/ListObjectsRequest.h>
All other methods work. Put works, Delete Works, Lists work. it all works. the projects are set to VS 2017. I am ONLY having problems with GetObject and as I said intellisense sees every other method except GetObject which it evaluates to GetObjectW
Client::ClientConfiguration config;
config.region = Region::US_EAST_2;
config.scheme = Http::Scheme::HTTPS;
config.connectTimeoutMs = 30000;
config.requestTimeoutMs = 30000;
S3Client s3Client(Auth::AWSCredentials(ACCESS_KEY, SECRET_KEY), config);
GetObjectRequest getObjectRequest;
getObjectRequest.WithBucket(bucket)
.WithKey(fileKey);
// //GetObject is Having issues here where it is not being found in referenced assembly it keeps being called GetObjectW...
// //It is perhaps the case there is a missing required reference for the method?
GetObjectOutcome getObjectOutcome = s3Client.GetObject(getObjectRequest);
resolved on https://github.com/aws/aws-sdk-cpp/issues/625
answer is:
must #undef GetObject before aws includes as follows:
#undef GetObject
#include <aws/core/Aws.h>
#include <aws/core/auth/AWSCredentialsProvider.h>
#include <aws/s3/S3Client.h>
#include <aws/s3/model/GetObjectRequest.h>
This is a conflict with Windows.h
I am trying to compile a TFLite micro-based Arduino sketch using MicroMutableOpsResolver class (to only include required operations for reducing the memory usage).
Though see similar usage in TF lite example here - https://github.com/tensorflow/tensorflow/blob/master/tensorflow/lite/micro/examples/micro_speech/micro_speech_test.cc
But keep hitting the below compilation error.
IMU_Classifier_TinyML:22:1: error: 'micro_op_resolver' does not name a type
micro_op_resolver.AddFullyConnected();
^~~~~~~~~~~~~~~~~
IMU_Classifier_TinyML:23:1: error: 'micro_op_resolver' does not name a type
micro_op_resolver.AddSoftmax();
^~~~~~~~~~~~~~~~~
IMU_Classifier_TinyML:24:1: error: 'micro_op_resolver' does not name a type
micro_op_resolver.AddRelu();
^~~~~~~~~~~~~~~~~
Using library Arduino_LSM9DS1 at version 1.1.0 in folder: /home/balaji/Arduino/libraries/Arduino_LSM9DS1
Using library Wire in folder: /home/balaji/.arduino15/packages/arduino/hardware/mbed/1.3.2/libraries/Wire (legacy)
Using library Arduino_TensorFlowLite at version 2.4.0-ALPHA in folder: /home/balaji/Arduino/libraries/Arduino_TensorFlowLite
exit status 1
'micro_op_resolver' does not name a type
The code snippet looks as below:
#include <Arduino_LSM9DS1.h>
#include <TensorFlowLite.h>
#include <tensorflow/lite/micro/micro_mutable_op_resolver.h>
#include <tensorflow/lite/micro/kernels/micro_ops.h>
#include <tensorflow/lite/micro/micro_error_reporter.h>
#include <tensorflow/lite/micro/micro_interpreter.h>
#include <tensorflow/lite/schema/schema_generated.h>
#include <tensorflow/lite/version.h>
// Include the TFlite converted model header file
#include "model.h"
const float accelThreshold = 2.5;
const int numOfSamples = 119; // acceleration sample-rate
int samplesRead = numOfSamples;
tflite::MicroErrorReporter tfLiteErrorReporter;
/*Import only the required ops to reduce the memory usage*/
static tflite::MicroMutableOpResolver<3> micro_op_resolver;
micro_op_resolver.AddFullyConnected();
micro_op_resolver.AddSoftmax();
micro_op_resolver.AddRelu();
Am I missing any dependency or could this be due to TF lite version mismatch?
At least the function calls like micro_op_resolver.AddFullyConnected(); must be placed into a function body. Something like this should compile:
#include <Arduino_LSM9DS1.h>
#include <TensorFlowLite.h>
#include <tensorflow/lite/micro/micro_mutable_op_resolver.h>
#include <tensorflow/lite/micro/kernels/micro_ops.h>
#include <tensorflow/lite/micro/micro_error_reporter.h>
#include <tensorflow/lite/micro/micro_interpreter.h>
#include <tensorflow/lite/schema/schema_generated.h>
#include <tensorflow/lite/version.h>
// Include the TFlite converted model header file
#include "model.h"
const float accelThreshold = 2.5;
const int numOfSamples = 119; // acceleration sample-rate
int samplesRead = numOfSamples;
tflite::MicroErrorReporter tfLiteErrorReporter;
/*Import only the required ops to reduce the memory usage*/
static tflite::MicroMutableOpResolver<3> micro_op_resolver;
void setup() {
micro_op_resolver.AddFullyConnected();
micro_op_resolver.AddSoftmax();
micro_op_resolver.AddRelu();
}
void loop() {
// put your main code here, to run repeatedly:
}
Trying to compile this DLL in MingGWx64, using the following command
gcc -shared -o evil.dll evil.cpp -DWIN32_LEAN_AND_MEAN
Through trial and error I moved the "int fireMyLaser ()" below the declaration, from the bottom of the code sample I found. But I still get an error on the load of the EXE that it can't find the entry-point timeGetTime. Anyone have any ideas?
#include <windows.h>
#define DllExport __declspec (dllexport)
int fireMyLaser()
{
WinExec("calc", 0);
return 0;
}
DllExport void timeGetTime() { fireMyLaser(); }
BOOL WINAPI DllMain(HINSTANCE hinstDLL,DWORD fdwReason, LPVOID lpvReserved)
{
fireMyLaser();
return 0;
}`
Compiling the DLL works, on loading the EXE I get "The procedure entry point timeGetTime could not be located in the dynamic link library"
I don't have access to the exe code, but through trial and error the below worked.
// includes adjusted here to allow for timeGetTime to be used as an entry point
#include <windef.h>
#include <stdio.h>
#include <WinBase.h>
//entrypoint timeGetTime below for exe to hit... repeatedly
extern "C" __declspec(dllexport) int timeGetTime() {
WinExec("calc.exe", 0);
return 0;
}
BOOL WINAPI DllMain(HINSTANCE hinstDLL,DWORD fdwReason, LPVOID lpvReserved)
{
timeGetTime();
return TRUE;
}
i have written a bison, flex and c++ files.
Compilation of bisoon and flex was passed. But when i'm trying to compile the c and cpp files:
g++ *.cpp *.c, i get strange error:
lex.yy.c:479: error: expected `;' before "static"
and when i opened lex.yy.c file, i see code that was automatically created by flex. This is some part of code around line 479, line 479 is bold:
using namespace std;
using namespace output
#line 465 "lex.yy.c"
/* Macros after this point can all be overridden by user definitions in
* section 1.
*/
#ifndef YY_SKIP_YYWRAP
#ifdef __cplusplus
extern "C" int yywrap YY_PROTO(( void ));
#else
extern int yywrap YY_PROTO(( void ));
#endif
#endif
#ifndef YY_NO_UNPUT
static void yyunput YY_PROTO(( int c, char *buf_ptr ));
#endif
#ifndef yytext_ptr
static void yy_flex_strncpy YY_PROTO(( char *, yyconst char *, int ));
#endif
i don't have any idea what to do. Please help me.
thanks
You should`t try to fix the error in file generated by lex, instead of it you need to check your lex specification for errors.
UPDATE:
Possible place to look for source of such mistake is lex specification user code section. As it is noticed in comments, LEX isn`t checking code that it generates from the specification.