FormatMessageA(...FORMAT_MESSAGE_ALLOCATE_BUFFER..) seems not to be understood

[Martin Poupě]

Hello,
have routine:

static void PrintFailed(const char *pszText)
{
    DWORD dwLastError = GetLastError();
    char *pszErrorMessage = NULL;
    const DWORD dwFlags = FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_MAX_WIDTH_MASK;
    FormatMessageA(dwFlags,NULL, dwLastError, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),(LPSTR)&pszErrorMessage, 0, NULL);
    fprintf(stderr,"%s failed. Error: %lu (%s)\n", pszText,dwLastError,pszErrorMessage ? pszErrorMessage : "?");
    LocalFree(pszErrorMessage);
}

cppcheck 2.16 says:

tmp.c:12:72: style: Condition 'pszErrorMessage' is always false [knownConditionTrueFalse]
    fprintf(stderr,"%s failed. Error: %lu (%s)\n", pszText,dwLastError,pszErrorMessage ? pszErrorMessage : "?");
                                                                       ^
tmp.c:9:29: note: Assignment 'pszErrorMessage=NULL', assigned value is 0
    char *pszErrorMessage = NULL;
                            ^
tmp.c:12:72: note: Condition 'pszErrorMessage' is always false
    fprintf(stderr,"%s failed. Error: %lu (%s)\n", pszText,dwLastError,pszErrorMessage ? pszErrorMessage : "?");

Also online demo complains:
[test.cpp:7]: (style) Condition 'pszErrorMessage' is always false
However the pszErrorMessage variable is allocated by FormatMessageA() call.

[CHR]

You should pass --library=windows, since windows.cfg has configuration for FormatMessageA.

[Martin Poupě]

Yes, it works now:-) Thank you for help.:-)