[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #21 from Jan Hubicka hubicka at gcc dot gnu.org 2012-03-25 09:39:38 UTC --- Author: hubicka Date: Sun Mar 25 09:39:32 2012 New Revision: 185774 URL: http://gcc.gnu.org/viewcvs?root=gccview=revrev=185774 Log: PR middle-end/51737 * cgraph.c (cgraph_remove_node_and_inline_clones): Add FORBIDDEN_NODE parameter. * cgraph.h (cgraph_remove_node_and_inline_clones): Update prototype. * ipa-inline-transform.c (save_inline_function_body): Remove copied clone if needed. * tree-inline.c (delete_unreachable_blocks_update_callgraph): Update. PR middle-end/51737 * g++.dg/torture/pr51737.C: New testcase Modified: branches/gcc-4_6-branch/gcc/ChangeLog branches/gcc-4_6-branch/gcc/cgraph.c branches/gcc-4_6-branch/gcc/cgraph.h branches/gcc-4_6-branch/gcc/cgraphunit.c branches/gcc-4_6-branch/gcc/testsuite/ChangeLog branches/gcc-4_6-branch/gcc/tree-inline.c
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 Jan Hubicka hubicka at gcc dot gnu.org changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution||FIXED --- Comment #22 from Jan Hubicka hubicka at gcc dot gnu.org 2012-03-25 09:40:05 UTC --- Fixed.
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #23 from Jan Hubicka hubicka at gcc dot gnu.org 2012-03-25 13:25:56 UTC --- Author: hubicka Date: Sun Mar 25 13:25:51 2012 New Revision: 185776 URL: http://gcc.gnu.org/viewcvs?root=gccview=revrev=185776 Log: PR middle-end/51737 * g++.dg/torture/pr51737.C: New testcase Added: trunk/gcc/testsuite/g++.dg/torture/pr51737.C
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #19 from Jan Hubicka hubicka at gcc dot gnu.org 2012-03-22 14:33:37 UTC --- Author: hubicka Date: Thu Mar 22 14:33:27 2012 New Revision: 185694 URL: http://gcc.gnu.org/viewcvs?root=gccview=revrev=185694 Log: PR middle-end/51737 * cgraph.c (cgraph_remove_node_and_inline_clones): Add FORBIDDEN_NODE parameter. * cgraph.h (cgraph_remove_node_and_inline_clones): Update prototype. * ipa-inline-transform.c (save_inline_function_body): Remove copied clone if needed. * tree-inline.c (delete_unreachable_blocks_update_callgraph): Update. PR middle-end/51737 * g++.dg/torture/pr51737.C: New testcase Modified: trunk/gcc/ChangeLog trunk/gcc/cgraph.c trunk/gcc/cgraph.h trunk/gcc/ipa-inline-transform.c trunk/gcc/testsuite/ChangeLog trunk/gcc/tree-inline.c
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #20 from Jan Hubicka hubicka at gcc dot gnu.org 2012-03-22 17:12:28 UTC --- I started to look into why the testcase does not fire on mainline. It seems to be effect of change in early inliner. We used to inline intrusive_ptr_release in early inlining ignoring the code size growth. This leads to large divergence of inlining decisions.
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #18 from Jan Hubicka hubicka at gcc dot gnu.org 2012-03-20 16:19:55 UTC --- Created attachment 26932 -- http://gcc.gnu.org/bugzilla/attachment.cgi?id=26932 patch in testing I am testing the attached patch. It basically delays removal of the clone until after the body saving process is finished. The problem is still on trunk, just the testcase passes because we optimize it too early.
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 Jakub Jelinek jakub at gcc dot gnu.org changed: What|Removed |Added Target Milestone|4.6.3 |4.6.4 --- Comment #17 from Jakub Jelinek jakub at gcc dot gnu.org 2012-03-01 14:38:29 UTC --- GCC 4.6.3 is being released.
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #12 from Richard Guenther rguenth at gcc dot gnu.org 2012-02-29 12:09:19 UTC --- The question is why we call delete_unreachable_blocks from tree_function_versioning at all. We do not bother updating the callgraph anywhere else. Honza, you added that beast?
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #13 from Jan Hubicka hubicka at ucw dot cz 2012-02-29 15:01:31 UTC --- The question is why we call delete_unreachable_blocks from tree_function_versioning at all. We do not bother updating the callgraph anywhere else. Honza, you added that beast? Well, after clonning we alter CFG and we need to update SSA for which we need to update dominators and those needs unreachable blocks gone. I will look into this. Honza
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 Jan Hubicka hubicka at gcc dot gnu.org changed: What|Removed |Added Status|NEW |ASSIGNED AssignedTo|unassigned at gcc dot |hubicka at gcc dot gnu.org |gnu.org | --- Comment #14 from Jan Hubicka hubicka at gcc dot gnu.org 2012-02-29 15:15:46 UTC --- mine.
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #15 from Richard Guenther rguenth at gcc dot gnu.org 2012-02-29 15:17:33 UTC --- (In reply to comment #13) The question is why we call delete_unreachable_blocks from tree_function_versioning at all. We do not bother updating the callgraph anywhere else. Honza, you added that beast? Well, after clonning we alter CFG and we need to update SSA for which we need to update dominators and those needs unreachable blocks gone. I will look into this. Ok - but why bother updating the callgraph?
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #16 from Jan Hubicka hubicka at ucw dot cz 2012-02-29 15:24:18 UTC --- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #15 from Richard Guenther rguenth at gcc dot gnu.org 2012-02-29 15:17:33 UTC --- (In reply to comment #13) The question is why we call delete_unreachable_blocks from tree_function_versioning at all. We do not bother updating the callgraph anywhere else. Honza, you added that beast? Well, after clonning we alter CFG and we need to update SSA for which we need to update dominators and those needs unreachable blocks gone. I will look into this. Ok - but why bother updating the callgraph? Because the edges still hold important information about inlining and redirecting, so we can not rebuild callgraph because the info would be lost. Ignoring the update would result in ill formed callgraph with missing/stale edges that is probably way to hell, too. So I opted to write code to keep it up to date. This is all part of the materialization clones: we do have virtual clones of single function, each with different parameters and different redirection of it. With materialization we need to build the bodies in one step, update the call according to edge redirection in following step and finally inline before doing the local optimization. Callgrpah needs to stay intact over the whole process. (and as we discussed, we may want to make it intact even longer ;) Honza
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #11 from Martin Jambor jamborm at gcc dot gnu.org 2012-01-09 22:42:00 UTC --- The problem is much more fundamental than just a clone removal while also walking the clones of the same function although that is the reason why we segfault. But that would be almost easy to solve. The bigger problem is indeed materialization of recursive loads itself: We have a function that calls itself twice and some of these calls and their calls are scheduled to be recursively inlined. When the decisions are to be carried out, we recognize we need to save a copy of the body to copy from somewhere and so we call save_inline_function_body. That function elects a clone to own the body copy and calls tree_function_versioning to copy it. And tree_function_versioning calls the problematic delete_unreachable_blocks_update_callgraph which analyzes CFG and finds some BBs unreachable - I'm not quite sure what made them so suddenly unreachable, but it almost certainly has something to do with EH BBs that somehow are stale at that point. And so the function begins to nuke respective call graph edges and also call graph nodes of respective inlined callees and their inlined callees and... and sure enough it decides to delete the node that save_inline_function_body chose to hold the new body, in other words it intends to delete id-dst_node of currently running tree_function_versioning. Thus even if we taught delete_unreachable_blocks_update_callgraph to be more careful about deleted nodes, tree_function_versioning would fail nevertheless. I'm wondering whether we could just skip delete_unreachable_blocks_update_callgraph when tree_function_versioning is called from within save_inline_function_body, though I can imagine the verifier could complain about something. I have to run now, will experiment more tomorrow.
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 Martin Jambor jamborm at gcc dot gnu.org changed: What|Removed |Added CC||hubicka at gcc dot gnu.org --- Comment #10 from Martin Jambor jamborm at gcc dot gnu.org 2012-01-06 12:02:04 UTC --- This bug is not triggered when IPA-SRA is switched off, however, from what I have seen in the debugger, I don't think the bug is in IPA-SRA but that it is in fact an inlining problem (and also very probably just latent on trunk). The immediate reason for the segfault is that one of very many inline clones of intrusive_ptrT::~intrusive_ptr() [with T = file_info] have NULL clone_of pointer. Looking more into why, I noticed that immediately before the crash id-dst_node-clones is NULL too, which should not happen since this code is guarded by a condition that this pointer is not NULL. Therefore I assume that the real problem is that it is not safe to call cgraph_remove_node_and_inline_clones on inlined recursive edges from delete_unreachable_blocks_update_callgraph since it destroys the clone tree we are traversing. Currently I do not know what to do about this other than push the nodes to be deleted on a stack and remove after the traversal. Honza, do you have a better idea?
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 --- Comment #9 from Martin Jambor jamborm at gcc dot gnu.org 2012-01-05 16:16:29 UTC --- I can reproduce the segfault when compiling both the testcase from comment #8 and the original unreduced test case on the 4.6 branch but not on my trunk checkout (revision 182785). I will have a look at what is going on nevertheless.
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737 Richard Guenther rguenth at gcc dot gnu.org changed: What|Removed |Added Status|UNCONFIRMED |NEW Last reconfirmed||2012-01-03 Component|c++ |tree-optimization Known to work||4.5.3 Target Milestone|--- |4.6.3 Summary|g++ crashes (internal |[4.6 Regression] g++ |compiler error: |crashes (internal compiler |Segmentation fault) when|error: Segmentation fault) |compiling quickbook |when compiling quickbook Ever Confirmed|0 |1 --- Comment #7 from Richard Guenther rguenth at gcc dot gnu.org 2012-01-03 09:21:16 UTC --- Confirmed (on the unreduced testcase) with 4.6.2 and the 4.6 branch head with just -O2: #0 0x00b7f910 in delete_unreachable_blocks_update_callgraph ( id=optimized out) at /space/rguenther/src/svn/gcc-4_6-branch/gcc/tree-inline.c:4972 #1 0x00b8d2b0 in tree_function_versioning (old_decl=0x71f18f00, new_decl=0x70649600, tree_map=optimized out, update_clones=128 '\200', args_to_skip=optimized out, blocks_to_copy=0x0, new_entry=0x0) at /space/rguenther/src/svn/gcc-4_6-branch/gcc/tree-inline.c:5232 #2 0x00b52961 in save_inline_function_body (node=0x71886160) at /space/rguenther/src/svn/gcc-4_6-branch/gcc/cgraphunit.c:2149 #3 0x00b5c1f8 in inline_transform (node=0x71886160) at /space/rguenther/src/svn/gcc-4_6-branch/gcc/ipa-inline.c:2122 #4 inline_transform (node=0x71886160) at /space/rguenther/src/svn/gcc-4_6-branch/gcc/ipa-inline.c:2108 does not reproduce on trunk, but that may be artificial. Re-reducing.
[Bug tree-optimization/51737] [4.6 Regression] g++ crashes (internal compiler error: Segmentation fault) when compiling quickbook
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51737
Richard Guenther rguenth at gcc dot gnu.org changed:
What|Removed |Added
CC||jamborm at gcc dot gnu.org
Known to work||4.7.0
--- Comment #8 from Richard Guenther rguenth at gcc dot gnu.org 2012-01-03
15:59:53 UTC ---
Testcase, ICEs at -O2, works on trunk. The code we ICE on is the same
on the branch and trunk, so maybe the issue is still latent there or maybe
we fixed it elsewhere. -fno-ipa-sra fixes it on the branch.
templateclass T class intrusive_ptr {
public:
~intrusive_ptr() { intrusive_ptr_release( px ); }
T * px;
};
template typename T struct intrusive_base {
friend void intrusive_ptr_release(T* ptr) { delete ptr; }
};
struct section_info;
struct file_info : intrusive_basefile_info {
intrusive_ptrfile_info parent;
intrusive_ptrsection_info switched_section;
};
struct section_info : intrusive_basesection_info {
intrusive_ptrsection_info parent;
};
struct id_state {
void * start_file(void);
};
void * id_state::start_file(void) {
intrusive_ptrfile_info parent;
}
struct id_generation_data : intrusive_baseid_generation_data {
void child_length() const {}
};
void generate_id(id_generation_data generation_data)
{
generation_data.child_length();
}
