* [Bug gcov-profile/91601] gcov: ICE in handle_cycle, at gcov.c:699 happen which get code coverage with lcov.
[not found] <bug-91601-4@http.gcc.gnu.org/bugzilla/>
@ 2020-03-27 19:28 ` mpolacek at gcc dot gnu.org
2020-03-29 14:19 ` marxin at gcc dot gnu.org
` (4 subsequent siblings)
5 siblings, 0 replies; 6+ messages in thread
From: mpolacek at gcc dot gnu.org @ 2020-03-27 19:28 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91601
Marek Polacek <mpolacek at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |mpolacek at gcc dot gnu.org
--- Comment #13 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
The fix hasn't been backported to gcc 8 but the problem exists there too.
Martin, will you fix 8 too?
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug gcov-profile/91601] gcov: ICE in handle_cycle, at gcov.c:699 happen which get code coverage with lcov.
[not found] <bug-91601-4@http.gcc.gnu.org/bugzilla/>
2020-03-27 19:28 ` [Bug gcov-profile/91601] gcov: ICE in handle_cycle, at gcov.c:699 happen which get code coverage with lcov mpolacek at gcc dot gnu.org
@ 2020-03-29 14:19 ` marxin at gcc dot gnu.org
2020-03-29 17:19 ` cvs-commit at gcc dot gnu.org
` (3 subsequent siblings)
5 siblings, 0 replies; 6+ messages in thread
From: marxin at gcc dot gnu.org @ 2020-03-29 14:19 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91601
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Resolution|FIXED |---
Status|RESOLVED |NEW
Known to fail| |8.4.0
--- Comment #14 from Martin Liška <marxin at gcc dot gnu.org> ---
Ah, sorry, I probably wrongly identified which versions are affected. Yes, I'm
gonna backport that.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug gcov-profile/91601] gcov: ICE in handle_cycle, at gcov.c:699 happen which get code coverage with lcov.
[not found] <bug-91601-4@http.gcc.gnu.org/bugzilla/>
2020-03-27 19:28 ` [Bug gcov-profile/91601] gcov: ICE in handle_cycle, at gcov.c:699 happen which get code coverage with lcov mpolacek at gcc dot gnu.org
2020-03-29 14:19 ` marxin at gcc dot gnu.org
@ 2020-03-29 17:19 ` cvs-commit at gcc dot gnu.org
2020-03-29 17:20 ` marxin at gcc dot gnu.org
` (2 subsequent siblings)
5 siblings, 0 replies; 6+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2020-03-29 17:19 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91601
--- Comment #15 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-8 branch has been updated by Martin Liska
<marxin@gcc.gnu.org>:
https://gcc.gnu.org/g:40aa944391dfec4529fb6970b9e78d5805f88fc5
commit r8-10149-g40aa944391dfec4529fb6970b9e78d5805f88fc5
Author: Martin Liska <mliska@suse.cz>
Date: Sun Mar 29 19:19:09 2020 +0200
Backport 9297e013293e4d332fc7c40859ea4dd9616e0d88
Backport from mainline
2019-09-02 Martin Liska <mliska@suse.cz>
PR gcov-profile/91601
* gcov.c (path_contains_zero_cycle_arc): Rename to ...
(path_contains_zero_or_negative_cycle_arc): ... this and handle
also negative edges.
(circuit): Handle also negative edges as they can happen
in some situations.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug gcov-profile/91601] gcov: ICE in handle_cycle, at gcov.c:699 happen which get code coverage with lcov.
[not found] <bug-91601-4@http.gcc.gnu.org/bugzilla/>
` (2 preceding siblings ...)
2020-03-29 17:19 ` cvs-commit at gcc dot gnu.org
@ 2020-03-29 17:20 ` marxin at gcc dot gnu.org
2020-09-16 1:09 ` i at maskray dot me
2020-10-19 12:17 ` marxin at gcc dot gnu.org
5 siblings, 0 replies; 6+ messages in thread
From: marxin at gcc dot gnu.org @ 2020-03-29 17:20 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91601
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Resolution|--- |FIXED
Status|NEW |RESOLVED
Known to fail|8.4.0 |
Known to work| |8.4.1
--- Comment #16 from Martin Liška <marxin at gcc dot gnu.org> ---
Fixed on GCC 8 branch.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug gcov-profile/91601] gcov: ICE in handle_cycle, at gcov.c:699 happen which get code coverage with lcov.
[not found] <bug-91601-4@http.gcc.gnu.org/bugzilla/>
` (3 preceding siblings ...)
2020-03-29 17:20 ` marxin at gcc dot gnu.org
@ 2020-09-16 1:09 ` i at maskray dot me
2020-10-19 12:17 ` marxin at gcc dot gnu.org
5 siblings, 0 replies; 6+ messages in thread
From: i at maskray dot me @ 2020-09-16 1:09 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91601
Fangrui Song <i at maskray dot me> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |i at maskray dot me
--- Comment #17 from Fangrui Song <i at maskray dot me> ---
The algorithm is Donald B. Johnson's "Finding all the elementary circuits of a
directed graph" (1975). (Hawick and James's just implemented the same algorithm
by changing the representation of graphs).
I am wondering why we enumerate every elementary cycle, find the minimum edge,
reduce edge weighs, and repeat the process.
What do we lose if we don't use the costly algorithm? (The time complexity is
O(n*e*(c+1)). However, many implementations (Boost and gcov.c) do not use a
hash set for the blocked list, and thus I suspect the actual complexity is
higher). Do we have other low-cost approaches? (e.g. repeatedly finding
strongly connected components and reducing)
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug gcov-profile/91601] gcov: ICE in handle_cycle, at gcov.c:699 happen which get code coverage with lcov.
[not found] <bug-91601-4@http.gcc.gnu.org/bugzilla/>
` (4 preceding siblings ...)
2020-09-16 1:09 ` i at maskray dot me
@ 2020-10-19 12:17 ` marxin at gcc dot gnu.org
5 siblings, 0 replies; 6+ messages in thread
From: marxin at gcc dot gnu.org @ 2020-10-19 12:17 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91601
--- Comment #18 from Martin Liška <marxin at gcc dot gnu.org> ---
(In reply to Fangrui Song from comment #17)
> The algorithm is Donald B. Johnson's "Finding all the elementary circuits of
> a directed graph" (1975). (Hawick and James's just implemented the same
> algorithm by changing the representation of graphs).
>
> I am wondering why we enumerate every elementary cycle, find the minimum
> edge, reduce edge weighs, and repeat the process.
I basically taken the original patch submission and finished it.
>
> What do we lose if we don't use the costly algorithm? (The time complexity
> is O(n*e*(c+1)). However, many implementations (Boost and gcov.c) do not use
> a hash set for the blocked list, and thus I suspect the actual complexity is
> higher). Do we have other low-cost approaches? (e.g. repeatedly finding
> strongly connected components and reducing)
Do you have a test-case where it is significant?
Feel free to provide a patch which can make it faster, I'll appreciate and
review it.
^ permalink raw reply [flat|nested] 6+ messages in thread