On Wed, May 08, 2019 at 01:45:25PM +0200, Johannes Schindelin wrote: > Hi René, > > On Thu, 2 May 2019, René Scharfe wrote: > > > Am 27.04.19 um 01:27 schrieb Johannes Schindelin via GitGitGadget: > > > From: Johannes Schindelin <johannes.schinde...@gmx.de> > > > > > > They really are unsigned, and we are using e.g. BLOCKSIZE as `size_t` > > > parameter to pass to `write_or_die()`. > > > > True, but the compiler converts that value correctly to size_t without > > complaint already, doesn't it? What am I missing? > > Are you talking about a specific compiler? It sure sounds as if you did. > > I really do not want to fall into the "you can build Git with *any* > compiler, as long as that compiler happens to be GCC, oh, and as long it > is version X" trap.
I don't this this has anything to do with gcc. The point is that we already have this line: write_or_die(fd, buf, BLOCKSIZE); which does not cast and nobody has complained, even though the signed constant is implicitly converted to a size_t. So adding another line like: gzwrite(gzip, block, BLOCKSIZE); would in theory be treated the same (gzwrite takes an "unsigned"). The conversion from signed to unsigned is well defined in ANSI C, and I'd expect a compiler to either complain about neither or both (and the latter probably with warnings like -Wconversion cranked up). But of course if you have data otherwise, we can revise that. Was the cast added out of caution, or to squelch a compiler warning? -Peff
