Hi, Sergey,


On 20.12.2024 15:15, Sergey Kaplun wrote:
Hi, Sergey!
Thanks for the review!
See my answers below.

On 20.12.24, Sergey Bronnikov wrote:
Hello, Sergey,

thanks for the patch! See comments below.


On 19.12.2024 12:30, Sergey Kaplun wrote:
The `strtod parsing` subtest in the <lib/base/tonumber_scan.lua> checks
the results yielded by the `strtod()` via FFI call. In glibc versions
before 2.28 it returns an incorrect result (NaN instead of inf) for
"0x3p1023" [1]. This patch hardens the skipcond for this test for a
smaller version of the libc installed.

[1]:https://sourceware.org/bugzilla/show_bug.cgi?id=23279
---

Branch:https://github.com/tarantool/luajit/tree/skaplun/gh-noticket-fix-glibc-versions

The CI failure for libc 2.23 (ubuntu 16):
https://github.com/tarantool/tarantool/actions/runs/12376159316/job/34542626889?pr=10949#step:5:13916
Ubuntu 16.04 EOL and EOS are reached [1]
The CI failure for libc 2.24 (debian 9):
https://github.com/tarantool/tarantool/actions/runs/12376159307/job/34542633454?pr=10949#step:5:13859
Debian 9 EOL is reached 4 years ago [2]
The CI failure for libc 2.27 (ubuntu 18):
https://github.com/tarantool/tarantool/actions/runs/12376159278/job/34542625496?pr=10949#step:5:11743
The CI pass for libc 2.31 (ubuntu 20):
https://github.com/tarantool/tarantool/actions/runs/12376159289/job/34542630993?pr=10949
Ubuntu 20.04 support ends in 3 months and 2 week [1].
Yes, unfortunately we should keep (AFAICS) these runners to check the
installations for our customers.

I believe we will clarify a list of Linux distros in a separate activity.



  test/LuaJIT-tests/lib/base/tonumber_scan.lua | 8 +++++---
  1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/test/LuaJIT-tests/lib/base/tonumber_scan.lua b/test/LuaJIT-tests/lib/base/tonumber_scan.lua
index ac7d68a4..800c57b0 100644
--- a/test/LuaJIT-tests/lib/base/tonumber_scan.lua
+++ b/test/LuaJIT-tests/lib/base/tonumber_scan.lua
@@ -186,9 +186,11 @@ do --- tonumber parsing
    test_conv(tonumber)
  end
  
--- Skip for the old libc version with the bug in the `strtod()`.
--- See alsohttps://sourceware.org/bugzilla/show_bug.cgi?id=16151.
-do --- strtod parsing -libc<2.19
+-- Skip for the old libc version with the bugs in the `strtod()`.
+-- Affected versions:
+-- * <2.19:https://sourceware.org/bugzilla/show_bug.cgi?id=16151.
+-- * <2.28:https://sourceware.org/bugzilla/show_bug.cgi?id=23279.
I propose to skip strtod test when Glibc is older than say 2.30 [3] and 
avoid testing

with ancient Glibc versions because Glibc implementation is buggy [4] and

a there are lot of bugs in old and more or less new versions:

v2.41 [5], v2.22 [6], v2.27 [7], v2.15 [8], v2.33 [9] etc [10].


I don't think we should waste our time with issues like this.


1. https://endoflife.date/ubuntu

2. https://endoflife.date/debian

3. https://sourceware.org/glibc/wiki/Release

4. 
https://github.com/tarantool/luajit/blob/cd5ab5da9b56bf560407554c0377cfa8567d4430/src/lj_strscan.c#L20-L27

5. https://sourceware.org/bugzilla/show_bug.cgi?id=30220

6. https://sourceware.org/bugzilla/show_bug.cgi?id=19380

7. https://sourceware.org/bugzilla/show_bug.cgi?id=15744

8. https://sourceware.org/bugzilla/show_bug.cgi?id=14049

9. https://sourceware.org/bugzilla/show_bug.cgi?id=26137

10. 
https://sourceware.org/bugzilla/buglist.cgi?bug_status=__all__&content=strtod&no_redirect=1&order=bug_id%20DESC&product=glibc&query_format=specific
Yes, I agree that this should be the last red line for us. If the test
will fail again due to glibc, it will be easier just to drop it. For
now, I see no failures for versions 2.31 -- 2.40, and find no bugs
related to our tests that affected versions 2.28 -- 2.30, so let's skip
it for versions less than 2.28 for now.

Okay, LGTM then.

Also discussed it and decided to remove the test if the same issue will happen next time.



        
+do --- strtod parsing -libc<2.28
    test_conv(function(s)
      local d = ffi.C.strtod(s, e)
      return (e[0][0] == 0 and #s ~= 0) and d or nil