On 9/6/2021 2:07 PM, Corinna Vinschen via Cygwin wrote:
On Sep 6 19:59, Corinna Vinschen via Cygwin wrote:
On Sep 6 13:38, Ken Brown via Cygwin wrote:
On 9/6/2021 1:12 PM, Ken Brown via Cygwin wrote:
On 9/6/2021 11:32 AM, Corinna Vinschen via Cygwin wrote:
On Sep 5 09:24, Ken Brown via Cygwin wrote:
On 9/4/2021 8:04 PM, Ken Brown via Cygwin wrote:
On 9/4/2021 6:58 PM, Ken Brown via Cygwin wrote:
Here are the correct commits:
8169e39ab Cygwin: C++17: register keyword is deprecated
3ca80b360 Cygwin: dumper: fix up GCC pragma for g++ 11.2
bdb7991db Cygwin: workaround a g++ 11.2 initialization bug
801120c1f Cygwin: loader script: add DWARF 5 sections
d5cc66426 Cygwin: testsuite: avoid "conflicting types" gcc warning
c2fe205b5 strstr: avoid warnings
76c2c7a89 ldexp/ldexpf: avoid assembler warning
eeeb5650c Cygwin: fix declaration of RtlInitEmptyUnicodeString
So there appears to be something wrong with cygwin1.dll
built with the current build tools (gcc 11.2.0, binutils
2.37, not sure what else is relevant).
Wait a minute...I'll bet this is related to the MEM_EXTENDED_PARAMETER
initialization problem that was dealt with in commit bdb7991db.
More data: When I run the test case under gdb, it succeeds. When I run it
under strace, I see VirtualAlloc2 in fhandler_dev_zero::mmap failing with
windows error 87.
Are the const's I added to the MEM_EXTENDED_PARAMETER data invalid,
perhaps?
I tried removing them, and I got the same error. I also tried removing
static, and I tried removing both static and const.
BTW, when I reported that the test case succeeds under gdb, that only
happens when I build the test case without optimization. If I build with
-O2, it fails under gdb also. [In all my tests, I built cygwin1.dll without
optimization.] This makes no sense to me at all.
Good hint. I found the culprit. With optimization, the code doesn't
set the "Reserved" bits in the first struct of MEM_EXTENDED_PARAMETER
to 0.
No, wait. I get what you say. The optimzation settings of the test
case should have no influence on the code inside the DLL. That doesn't
make sense for sure. However, I ran the testcase under GDB, I could
reproduce the issue, and I could fix it by setting mmap_ext.Reserved = 0;
Go figure!
I don't get it, but I can confirm that the problem is fixed.
Thanks.
Ken
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