On Sun, Nov 23, 2014 at 10:20:44PM +0000, Henrique Lengler wrote: > Hi, > > What is the situation of GCC, is it bloated?
Holy shit, yes! Ever tried to compile it? And in the end, GCC has a lot of optimizers that make pedantic asumptions about the code they compile. For instance, if i is of signed integer type, i + 1 can never be smaller than i. Yeah, right. Nevermind that this asumption removes most overflow checking code. I know that this case is undefined or implementation-defined or something, but... well, the problem is, most code out there is not strictly conforming to the C standard. For instance, did you know that converting a floating point value into an integer type where the integer part can not be represented causes undefined behavior? I didn't until recently. So converting an FP value that might be negative to an unsigned type is undefined, but converting an FP value that is definitly in range to a signed integer type and that to an unsigned integer type is completely defined. What? u = fp; is undefined, but u = (int)fp; is not? > I'm asking because I don't find too much on suckless site about it > I don't have experience in any other compiler. > Well, there's always clang. It's completely written in C++, but is way better organized than GCC and it is contained entirely in a lib, so it can be easily integrated into IDEs and other programs. If you need a C parser, have a look at libclang. > I also found someday TCC (Tiny C compiler - bellard.org/tcc/) > And it looks cool. > Yeah, but good luck compiling anything with it that requires GCC extensions. See, GCC is bloated, but there is also a reason for that: It is written to be as commonly usable as possible. Why do you think you need (at last count) three different multi-precision libraries to compile GCC? Because in the general case you cannot assume that the native types will be big enough to hold all the values of the target types. > The site shows the speed of it: > Compiler Time(s) lines/second MBytes/second > TinyCC 0.9.22 2.27 859000 29.6 > GCC 3.2 -O0 20.0 98000 3.4 > > What they don't talk about is the speed of execution, wich I think > is faster with gcc. But if I were create a suckless gcc I would > probably fork TCC. > > So what do you think, GCC is ok? Or no? > Oh, heavens, no! But it is a necessary evil. IIRC the linux kernel can only partially be compiled with clang (and tinycc doesn't stand a lick of a chance), so there is a necessity for gcc. Regarding execution time: Yes, with GCC that will be much better than with tinycc, because the former has way more and way more aggressive optimizers. By now, the only thing that really bugs me is that GCC's optimizers make code undebuggable. Or is that GDB's fault. > Regards, Ciao, Markus
