[Compile] 2, MinGW gcc in Windows build Win32 program Environment

1, ordinary download a MinGW program, after installation can directly copy the MinGW directory to the main project tool inside:

 demo_mesh_common tree -L 2.├── app├── bin├── build├── doc├── sdk│?? ├── alg│?? ├── bsp│?? ├── driver│?? └── phy└── tool    └── MinGW

2, the reference learning in DOS using GCC to compile, found that the step-up compilation will report _alloca undefined error:

a.o:a.c:(.text+0x3f8): undefined reference to `_alloca'

The guess is that some libraries do not have links in, so search for libraries under mingw/lib/:

F:\demo_mesh_common\tool\MinGW\lib>grep -rn "_alloc"Binary file libmingw32.a matchesBinary file libmingwex.a matchesBinary file libwldap32.a matchesBinary file libdxerr8.a matchesBinary file libdxerr9.a matchesBinary file gcc/mingw32/3.4.5/libgcc.a matchesBinary file librpcdce4.a matchesBinary file libbfd.a matchesBinary file libiberty.a matches

With an Add-in compilation option, the final discovery is: You need to add GCC/MINGW32/3.4.5/LIBGCC.A:

./MinGW/bin/ld -L"./MinGW/lib" -o a.exe a.o  "./MinGW/lib/crt2.o" -lmingw32 -lkernel32 -lmsvcrt -luser32 -lwow32 -lwldap32 -lwin32k -lvfw32 -lmingw32 -lmingwex -lwldap32 -ldxerr8 -ldxerr9 -lrpcdce4 -lbfd -liberty -L"./MinGW/lib/gcc/mingw32/3.4.5" -lgcc

3, I test the Win32 serial port program, in the Git Bush (Linux properties) window can be executed, but no data, must be executed in the win window.

4. Appendix

Makefile

a.o:a.c    ./MinGW/bin/gcc -c a.cB:a.o    ./MinGW/bin/ld -L"./MinGW/lib" -o a.exe a.o  "./MinGW/lib/crt2.o" -lmingw32 -lkernel32 -lmsvcrt -luser32 -lwow32 -lwldap32 -lwin32k -lvfw32 -lmingw32 -lmingwex -lwldap32 -ldxerr8 -ldxerr9 -lrpcdce4 -lbfd -liberty -L"./MinGW/lib/gcc/mingw32/3.4.5" -lgccA:    ./MinGW/bin/gcc -s -O2 a.c -mconsole

A.C:

#include <stdio.h> #include <stdlib.h> #include <windows.h> #include <string.h> #include < Malloc.h>handle hcomm;overlapped M_ov; Comstat Comstat;dword m_dwcommevents;//If the FILE_FLAG_OVERLAPPED flag is defined when calling CreateFile to create a handle Then calls to ReadFile and WriteFile to the handle in the//row should be overlapping, if the//overlap flag is not specified, then the read and write operation should be synchronous//at synchronous execution, the function will not return until the operation is completed. This means that the thread is blocked while the synchronization is executing, resulting in a decrease in efficiency from//. When overlapping execution, even if the operation is not completed, the two functions will return immediately, the fee//when the I/O operation in the background bool Openport (char *portname)//Open a serial port {Hcomm = CreateFile (PortName, Gener Ic_read |    Generic_write, 0, 0, open_existing, file_flag_overlapped, 0);    if (Hcomm = = INVALID_HANDLE_VALUE) return FALSE; else return TRUE;}    BOOL SETUPDCB (int rate_arg) {DCB DCB;    int rate= Rate_arg; memset (&dcb,0,sizeof (DCB)); Populating a given value in a block of memory is the quickest way to clear 0 operations on a larger structure//body or array if (!    Getcommstate (HCOMM,&AMP;DCB))//Get current DCB configuration {return FALSE;     }/*--------------------------------------------------------------------*//Set DCB to configure the serial port Dcb. DCBlength = sizeof (DCB); /*----------Serial Port Config-------*/DCB.    BaudRate = rate; Dcb.    Parity = noparity;    dcb.fparity = 0; Dcb.    StopBits = Onestopbit; Dcb.    ByteSize = 8;    Dcb.foutxctsflow = 0;    Dcb.foutxdsrflow = 0;    Dcb.fdtrcontrol = dtr_control_disable;    dcb.fdsrsensitivity = 0;    Dcb.frtscontrol = rts_control_disable;    DCB.FOUTX = 0;    Dcb.finx = 0;    /*-----------------Misc Parameters-----*/Dcb.ferrorchar = 0;    Dcb.fbinary = 1;    Dcb.fnull = 0;    Dcb.fabortonerror = 0;    dcb.wreserved = 0; Dcb.    Xonlim = 2; Dcb.    Xofflim = 4; Dcb.    XonChar = 0x13; Dcb.    XoffChar = 0x19; Dcb.    Evtchar = 0; /*--------------------------------------------------------------------*//Set DCB if (!    SetCommState (HCOMM,&AMP;DCB)) {return FALSE; } else return TRUE;} Read and write serial ports with ReadFile and WriteFile, you need to consider the time-out problem, read and write serial port timeout has two//species: Interval timeout and total timeout, write operation only supports the total timeout, and read operation two timeouts are supported, if all//write timeout parameters are 0, then the write timeout is not used. BOOL setuptimeout (DWORD readinterval,dword readtotalmultiplier,dword Readtotalconstant,dword WriteTotalMultiplier,    DWORD writetotalconstant) {commtimeouts timeouts; Timeouts. Readintervaltimeout=readinterval; Read interval timeout timeouts. Readtotaltimeoutconstant=readtotalconstant; Read time factor timeouts. Readtotaltimeoutmultiplier=readtotalmultiplier; Read time constant timeouts. Writetotaltimeoutconstant=writetotalconstant; Write time factor timeouts. Writetotaltimeoutmultiplier=writetotalmultiplier; Write Time constant//volume, the total timeout is calculated as: Total Timeout = time factor x number of characters required to read/write + TIME constant if (!    SetCommTimeouts (Hcomm, &timeouts)) {return FALSE; } else return TRUE;}    void Receivechar () {BOOL bRead = TRUE;    BOOL bresult = TRUE;    DWORD dwerror = 0;    DWORD bytesread = 0;    Char Rxbuff;    while (TRUE) {bresult = Clearcommerror (Hcomm, &dwerror, &comstat); You should use the Clearcommerror function to clear the error if (COMSTAT.CB) before using the ReadFile function for read operations.inque==0)//COMSTAT structure returns the serial port status information//This article only uses the Cbinque member variable, the value of this member variable represents the number of bytes in the input buffer continue; if (bRead) {bresult = ReadFile (Hcomm,//Handle to COMM port serial port handle &rxbuff,//RX Buffer pointer//read-in number According to the stored address, the read-in data is stored/stored in the memory area of the first address with the value of the pointer 1,//the number of bytes of data to read in read one byte, &bytesread,//Stores numbers O           F bytes read, which points to a dword//value that returns the number of bytes actually read in the read Operation &m_ov);        When the pointer to the M_ov structure//overlap operation, this parameter points to a overlapped structure, which is null when synchronizing the operation ("%02x", Rxbuff); if (!bresult) {///when ReadFile and WriteFile return false, it is not necessarily an operation loss//defeat, the thread should call the GetLastError function to parse the returned result switch (dwerror = Getlaste                    Rror ()) {case error_io_pending:bread = FALSE;            Break            Default:break;        }}else{bRead = TRUE;        }}//Close if (bRead) if (!bread) {bRead = TRUE;   Bresult = GetOverlappedResult (Hcomm,//Handle to COMM Port &m_ov, Overlapped structure &bytesread,//Stores number of bytes read TRUE);    Wait flag}}}bool Writechar (byte* m_szwritebuffer,dword m_ntosend) {BOOL bwrite = TRUE;    BOOL bresult = TRUE;    DWORD bytessent = 0;    HANDLE m_hwriteevent;    ResetEvent (m_hwriteevent); if (bwrite) {M_ov.    Offset = 0; M_ov.    Offsethigh = 0; Clear Buffer bresult = WriteFile (Hcomm,//Handle to COMM Port, handle of serial port M_szwritebuffer,//Pointer T                                o message buffer in calling Finction//That is, the value of the pointer to the first address Nnumberofbytestowrite bytes of data will be written to the serial port of the Send data buffer m_ntosend,//Length of message to send, the number of bytes to write data &am P BytesSent,//Where to store the number of bytes sent//point to a DWORD value that returns                The number of bytes actually written &m_ov); Overlapped structure//overlap operation, this parameter points to a Overlapped structure,//synchronous operation, this parameter is null if (!bresult) {///when ReadFile and WriteFile return False,        The thread should call the GetLastError function to parse the returned results DWORD dwerror = GetLastError (); Switch (dwerror) {case error_io_pending://getlasterror function returns//error_io_pending.                This indicates that the overlap operation has not yet completed//continue to getoverlappedresults () bytessent = 0;                Bwrite = FALSE;        Break        Default:break;    }}}//End if (bwrite) if (!bwrite) {bwrite = TRUE; Bresult = GetOverlappedResult (Hcomm,//Handle to COMM Port &m_ov,//Overlapped structure &am P             BytesSent,//Stores number of bytes sent TRUE);    Wait Flag//deal with the error code if (!bresult) {printf ("getoverlappedresults () in WriteFile ()"); }}//End if (!bwrite)//Verify that the data size of send equals what we tried to send if (bytessent! = m_  Ntosend) {  printf ("Warning:writefile () Error: Bytes Sent:%d;    Message Length:%d\n ", BytesSent, strlen ((char*) m_szwritebuffer)); } return TRUE;    int main (void) {printf ("Open comport successsdsfds\n");    if (Openport ("COM3")) printf ("Open comport success\n");    if (SETUPDCB (9600)) printf ("Setupdcb success\n");    if (Setuptimeout (0,0,0,0,0))///If all write timeout parameters are 0, then the write timeout of printf ("Setuptimeout success\n") is not used; PurgeComm (Hcomm, Purge_rxclear | Purge_txclear | Purge_rxabort | Purge_txabort);    Before reading and writing the serial port, also use the PurgeComm () function to empty the buffer//purge_txabort interrupt all writes and return immediately, even if the write operation is not completed.    Purge_rxabort interrupts all read operations and returns immediately, even if the read operation has not been completed.    Purge_txclear clears the output buffer//purge_rxclear clears the input buffer//writechar ("Please send the data now", 20);    printf ("Received data:\n");    Receivechar ();    System ("pause"); return 0;}

Link

• Learn to use GCC to compile under DOS: https://www.cnblogs.com/personnel/p/4584819.html

@beautifulzzzz智能硬件、物联网，热爱技术，关注产品博客：http://blog.beautifulzzzz.com园友交流群：414948975

[Compile] 2, MinGW gcc in Windows build Win32 program Environment