Andrew & Sebastian, Thank you very much for you help, guys!
It's easier to fix our source code anyway :-) Best Regards, --Ray -----Original Message----- From: Andrew Haley [mailto:[EMAIL PROTECTED] Sent: Friday, August 22, 2008 12:35 PM To: Sebastian Redl Cc: Balogh, Ray; [EMAIL PROTECTED] Subject: Re: GCC 2.95.3 bug Sebastian Redl wrote: > Balogh, Ray wrote: >> Dear GCC folks: >> >> I'm having a problem with GCC 2.95.3 that appears to be a compiler >> bug. It seems to be optimizing out inlined function code with side >> effects, and is related to binding a non-const pointer to a const >> pointer reference function parameter. The problem only happens with >> optimization on, and goes away with -O0. >> >> inline unsigned unpack2 (const byte *&data) >> { >> unsigned val = data[0] << 8 | data[1]; >> data += 2; >> return val; >> } >> inline unsigned unpack2 (const byte *&data, unsigned &count) >> { >> unsigned val = data[0] << 8 | data[1]; >> data += 2; >> count -= 2; >> return val; >> } >> >> void extractInfo (byte *&data, unsigned &datalen, >> unsigned &f1, unsigned &f2) >> { >> cout << "data = " << data << ", datalen = " << datalen << endl; >> f1 = unpack2 (data, datalen); >> cout << "data = " << data << ", datalen = " << datalen << endl; >> >> byte *peek = data; >> //const byte *peek = data; // **** Adding "const" works around >> the compiler problem **** >> // Another work-around is to uncomment >> the non-const f1 of unpack2() above >> >> unsigned tmp = datalen; >> cout << "peek = " << peek << ", tmp = " << tmp << endl; >> (void) unpack2 (peek, tmp); // skip over irrelevant field >> cout << "peek = " << peek << ", tmp = " << tmp << endl; >> (void) unpack2 (peek, tmp); // skip over irrelevant field >> cout << "peek = " << peek << ", tmp = " << tmp << endl; >> >> unsigned xlen = unpack2 (peek, tmp); >> cout << "peek = " << peek << ", tmp = " << tmp << endl; >> >> f2 = xlen; >> } >> > In my opinion, the bug is that this even compiles. It's invalid to write > char *pc; > const char **ppc = &pc; > > Why should it be valid to write > char *pc; > const char *&rpc = pc; > I agree. The code is invalid; modern g++ generates an error. Andrew.
