eli@smectos.gang.umass.edu (Eli Brandt) (06/15/91)
I took this out of the graphics groups cuz it's not graphics. In article <1991Jun12.201740.16463@netcom.COM> jls@netcom.COM (Jim Showalter) writes: [ Ada/C++ discussion axed ] >>o C++ compilers are cheap -- the GNU family is free, and runs >> on a number of different architectures. You can get the source >> code so that you can fix it if it's broken. > >You get what you pay for. Personally, I'd much prefer to buy a validated >compiler with the number of bugs approaching zero than use a free compiler >so shot full of bugs the source code is provided to me to patch around >problems that SHOULD have been taken care of by the vendor. Out of curiosity, have you actually used a GNU compiler? If so, could you specify some of the bugs with which it was "shot through". Please, only note those which directly affected you, because *commercial* compiler vendors don't tell you about other bugfixes. My experience has been that gcc is less buggy than Sun cc or (smirk) Microsoft C. I've had no problems working on a prospective Obfuscated C entry. Can you honestly tell me that you've never wanted to look at, tweak, port, or tinker with your compiler? Difficult without source. As for support, I suspect the net will be around longer than most Ada vendors. GCC sidenote: It appears that gcc -O generates division code which is about six times faster than SGI's cc -O on a 4D. Multiplication is "only" 70% faster. Has anybody else seen numbers like these? A factor of six seems just a bit odd. "You get what you pay for"? [ C++ bashing, much of which I agree with, axed ] >-- >*** LIMITLESS SOFTWARE, Inc: Jim Showalter, jls@netcom.com, (408) 243-0630 **** >*Proven solutions to software problems. Consulting and training on all aspects* >*of software development. Management/process/methodology. Architecture/design/* >*reuse. Quality/productivity. Risk reduction. EFFECTIVE OO usage. Ada/C++. * / Eli Brandt eli@gang.umass.edu \ \ You have been disclaimed. /
dhinds@elaine18.Stanford.EDU (David Hinds) (06/16/91)
In article <32088@dime.cs.umass.edu> eli@smectos.CS.UMASS.EDU (Eli Brandt) writes: >GCC sidenote: It appears that gcc -O generates division code which is about >six times faster than SGI's cc -O on a 4D. Multiplication is "only" 70% >faster. Has anybody else seen numbers like these? A factor of six seems >just a bit odd. What code, exactly, shows this big difference? It is not believable that two reasonable decent compilers should show a large difference in generated code to do a single primitive operation. Does the difference persist at -O3 with the MIPS compiler? It is not completely fair to compare GCC full optimization with the first level of MIPS optimization. I was especially surprised to see this claim, because in my experience, GCC -O3 code is 15-25% slower than than MIPS cc -float -O3 code on my applications. I occasionally use GCC to help trace down bugs, because I can get more warning messages, but I always use the MIPS compiler for compute-intensive code. -David Hinds dhinds@cb-iris.stanford.edu
certain@sgi.com (Andrew Certain) (06/18/91)
In article <32088@dime.cs.umass.edu> eli@smectos.CS.UMASS.EDU (Eli Brandt) writes: > >Out of curiosity, have you actually used a GNU compiler? If so, could you >specify some of the bugs with which it was "shot through". When I was taking a computer graphics course at the University of North Carolina - Chapel Hill, we switched from Sun's C++ to g++ and experienced several very annoying bugs. I can't remember what they all where, but one was the following: In a class header file, we declared two variables like so: ... image *image1; image *image2; ... If something was assigned to image2, the program seg faulted. It we then made the one change: ... image *image2; image *image1; ... Then the assignment to image2 worked, but assignments to image1 seg faulted. Andrew Certain certain@cs.unc.edu certain@sgi.com None of this posting reflects the opinions of my employer.
andru@myth.rad.sgi.com (Andrew Myers) (06/23/91)
In article <32088@dime.cs.umass.edu> eli@smectos.CS.UMASS.EDU (Eli Brandt) writes: >Out of curiosity, have you actually used a GNU compiler? If so, could you >specify some of the bugs with which it was "shot through". Please, only note Please read gnu.bug.g++. You will discover that I have personally posted about 10 bugs which exist in all released g++ implementations. Two of the bugs are so bad that they make g++ unusable for any serious work. No patches seem to exist for these bugs. My program works perfectly on AT&T C++. In my case, I would have to say that g++ gave me significantly less than what I paid for it. Andrew