SL>MSDN, SymGetLineFromAddr64, Remarks:
SL>

SL>The caller must allocate the Line buffer properly and fill in the required members of the IMAGEHLP_LINE64 structure before calling SymGetLineFromAddr64.

SL>MSDN, SymGetSymFromAddr64, Remarks:
SL>

SL>The caller must allocate the Symbol buffer properly and fill in the required parameters in the IMAGEHLP_SYMBOL64 structure before calling SymGetSymFromAddr64.

Ага, только вот пример если смотреть то там:

SymGetSymFromAddr64

DWORD  dwAddress;
DWORD  dwDisplacement;
BYTE   buffer[256];
PSYMBOL_INFO pSymbol = (PSYMBOL_INFO)buffer;

pSymbol->SizeOfStruct = sizeof(SYMBOL_INFO);
pSymbol->MaxNameLen = sizeof(buffer) - sizeof(SYMBOL_INFO) + 1;

if (SymFromAddr(hProcess, dwAddress, &dwDisplacement, pSymbol))
{
// SymFromAddr returned success
}
else
{
    // SymFromAddr failed
    error = GetLastError();
    printf("SymFromAddr returned error : %d\n", error);
}

SymGetLineFromAddr64

DWORD64  dwAddress;
DWORD  dwDisplacement;
IMAGEHLP_LINE64 line;

SymSetOptions(SYMOPT_LOAD_LINES);

line.SizeOfStruct = sizeof(IMAGEHLP_LINE64);

if (SymGetLineFromAddr64(hProcess, dwAddress, &dwDisplacement, &line))
{
    // SymGetLineFromAddr64 returned success
}
else
{
    // SymGetLineFromAddr64 failed
    error = GetLastError();
    printf("SymGetLineFromAddr64 returned error : %d\n", error);
}

Да и в других местах я видел, что под Line память выделяется только на стеке под структуру а под строку — нет