On Jul 2 10:37, Jeremy Drake via Cygwin-patches wrote: > On Wed, 2 Jul 2025, Corinna Vinschen wrote: > > > On Jun 30 10:11, Jeremy Drake via Cygwin-patches wrote: > > > On Mon, 30 Jun 2025, Corinna Vinschen wrote: > > > > > > > On Jun 27 10:34, Jeremy Drake via Cygwin-patches wrote: > > > > > On Fri, 27 Jun 2025, Corinna Vinschen wrote: > > > > > > > > > > > On Jun 26 13:31, Jeremy Drake via Cygwin-patches wrote: > > > > > > > BTW, I noticed while editing mingw/Makefile.am, shouldn't cygload > > > > > > > have > > > > > > > -Wl,--disable-high-entropy-va in LDFLAGS? > > > > > > > > > > > > Why? > > > > > > > > > > With high-entropy-va, it has been observed that the PEB, TEB and > > > > > stack can > > > > > happen to overlap with the cygheap > > > > > https://cygwin.com/pipermail/cygwin/2024-May/256000.html > > > > > > > > Yeah, but HEVA simply breaks fork. We don't have to test this, because > > > > it won't work and we don't do it. You can set the PE flag, but than > > > > you're on your own. > > > > > > Outside of fork, is cygheap able to "relocate" in case the memory it would > > > like to occupy is already used? > > > > I don't think so, without checking and, well, fixing every pointer usage > > potentially pointing into the cygheap. Even fhandlers have pointers to > > fhandlers... > > > > So shouldn't any user of the cygwin dll then need > -Wl,--disable-high-entropy-va to avoid the chance that Windows places its > structures where cygheap wants to be?
-Wl,--disable-high-entropy-va isn't required because gcc doesn't enable it by default on Cygwin. If newer versions do, it's a bug in these gcc versions. Corinna
