Parse -.x2. (unary -.) as -.(x2.). Fix PR#3414 #2

Chris00 · 2013-08-20T13:35:19Z

This is what is expected mathematically. Note that -2.**2. is parsed
as (-2.)**2. because -2. is considered to be a constant. However
-.2.**2. is parsed as -.(2.**2.).

amirmc · 2013-08-22T19:32:06Z

Cross-referencing the issue at http://caml.inria.fr/mantis/view.php?id=3414 (in case anyone else stumbles on this PR).

Is there here because the diff is easier to read? I'm just curious.

Chris00 · 2013-08-23T06:33:45Z

It is also easier to comment on individual lines and will be noticed by a larger audience — since it slightly changes the parsing of the language, I think it is good that many eyes check it.

This is what is expected mathematically. Note that -2.**2. is parsed as (-2.)**2. because -2. is considered to be a constant. However -.2.**2. is parsed as -.(2.**2.). Fix http://caml.inria.fr/mantis/view.php?id=3414

- Register type "Addr" is split into . "Val" (well-formed OCaml values, appropriate as GC roots) . "Addr" (derived pointers within the heap, must not survive a GC) - memory_chunk "Word" is split into . "Word_val" (OCaml value) . "Word_int" (native-sized integer, not a pointer into the heap) Cmmgen was updated to use Word_val or Word_int as appropriate. Application #1: fail at compile-time if a derived pointer within the heap survives a GC point (cf. PR#6484). Application #2: CSE can do a better job across allocation points (keep factoring expressions of type Int, Val, Float, but not Addr). git-svn-id: http://caml.inria.fr/svn/ocaml/branches/cmm-mach-types@15568 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

gasche · 2014-12-13T21:27:30Z

I think @planar 's comment in the corresponding mantis issue means we can consider the case closed on this one for now.

A general remark: we are very weary of changing the grammar because it's hard to tell how many programs this will break. In this particular case, the typechecker will not help at all in tracking the change, so programs will just start returning the wrong result without any hint of what is wrong.

I think it's pretty unlikely that we will ever dare to make this change.

git-svn-id: http://caml.inria.fr/svn/ocaml/version/4.02@15978 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

(Merge of branch cmm-mach-types and PR#115.) - Register type "Addr" is split into . "Val" (well-formed OCaml values, appropriate as GC roots) . "Addr" (derived pointers within the heap, must not survive a GC) - memory_chunk "Word" is split into . "Word_val" (OCaml value) . "Word_int" (native-sized integer, not a pointer into the heap) Cmmgen was updated to use Word_val or Word_int as appropriate. Application #1: fail at compile-time if a derived pointer within the heap survives a GC point (cf. PR#6484). Application #2: CSE can do a better job across allocation points (keep factoring expressions of type Int, Val, Float, but not Addr). Application #3: slightly fewer roots given to the GC (e.g. pointers into bigarray data). git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@16269 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

Add Gc.print_stat hook to std_exit.ml

Enable UTF-8 on Windows 10 Console (Mark #2)

Enable UTF-8 on Windows 10 Console (Mark #2) (cherry picked from commit 10b309f)

We expose a function to access the information in the Topdir API since this partially solves ocaml#2. A small change to misc.mli is needed to avoid exposing Misc in {T,Opt}optdirs interfaces.

Let's try with a very short timeout, to make sure the job will exceed it.

Multiway match typechecking and translation for pattern guards (ocaml#2) * multiway typechecking and translation * update jane test output * self-review: format and style in translcore * more translcore/typedtree cleanup * expose value `is_guarded_rhs` * fix typedtree printer * make discussed changes to ocamldoc * format: remove unnecessary parens in pattern * improve parmatch variable naming * explain [exp_attributes] and [exp_extra] weirdness * improve translcore [event_function*] naming * inlined transl_body in transl_rhs * rename pats_exp... to use "rhs" naming * added test for guarded value/exception or-patterns * address ocamldoc CRs --------- Co-authored-by: Nick Roberts <[email protected]>

add a tutorial and a meeting

Automatically generated. Merged on Netlify CMS.

* initial pipeline to include v3.ocaml.org site code * add extra dependencies * update opam-repository from the pipeline * make ocamlorg the only backend library * convert to use lwt syntax * Clean up formatting and dead code * Fix docker image reference * remove github oauth and init the ocurrent logs * Hide pipeline initialization from ocamlorg_web * Fix docker build Co-authored-by: Thibaut <[email protected]>

Reported by `-fsanitize=memory`: ``` > ==102752==WARNING: MemorySanitizer: use-of-uninitialized-value > #0 0x7f2ba7fb4ea4 in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:496:18 > #1 0x7f2ba7fbc016 in caml_ml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:1207:9 > ocaml#2 0x59ba5c in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 > ocaml#3 0x5a9220 in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 > ocaml#4 0x540d6b in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 > ocaml#5 0x7f2ba8120087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#6 0x7f2ba812014a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 617637580ee48eff08a2bce790e1667ad09f3b69) > > Uninitialized value was stored to memory at > #0 0x7f2ba7fb4e9d in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:497:69 > #1 0x7f2ba7fbc016 in caml_ml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:1207:9 > ocaml#2 0x59ba5c in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 > ocaml#3 0x5a9220 in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 > ocaml#4 0x540d6b in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 > ocaml#5 0x7f2ba8120087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#6 0x7f2ba812014a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 617637580ee48eff08a2bce790e1667ad09f3b69) > > Uninitialized value was created by an allocation of 'buf' in the stack frame > #0 0x7f2ba7fb3dbc in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:402:7 > ``` This is in fact an EV_LIFECYCLE with EV_RING_STOP, which has 0 additional data, and thus msg_length 2: ``` runtime/runtime_events.c: EV_RUNTIME, (ev_message_type){.runtime=EV_LIFECYCLE}, EV_RING_STOP, 0, ``` Attempting to read from `buf[2]` would read uninitialized data (or potentially beyond the end of the buffer). Check `msg_length` before reading. Signed-off-by: Edwin Török <[email protected]>

Bigarrays are printed in the toplevel as `<abstr>`, but ObjTbl.mem computes a hash. However bigarrays are uninitialized when allocated, so this seems to be a genuine bug: ``` ==133712==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x4e6d11 in caml_ba_hash /var/home/edwin/git/ocaml/runtime/bigarray.c:486:45 #1 0x52474a in caml_hash /var/home/edwin/git/ocaml/runtime/hash.c:251:35 ocaml#2 0x599ebf in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1065:14 ocaml#3 0x5a909a in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 ocaml#4 0x540ccb in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 ocaml#5 0x7f0910abb087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#6 0x7f0910abb14a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) Uninitialized value was created by a heap allocation #0 0x47d306 in malloc (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x47d306) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) #1 0x4e7960 in caml_ba_alloc /var/home/edwin/git/ocaml/runtime/bigarray.c:246:12 ocaml#2 0x4e801f in caml_ba_create /var/home/edwin/git/ocaml/runtime/bigarray.c:673:10 ocaml#3 0x59b8fc in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 ocaml#4 0x5a909a in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 ocaml#5 0x540ccb in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 ocaml#6 0x7f0910abb087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#7 0x7f0910abb14a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#8 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) SUMMARY: MemorySanitizer: use-of-uninitialized-value /var/home/edwin/git/ocaml/runtime/bigarray.c:486:45 in caml_ba_hash ``` Suppress it for now until a solution is found. The testsuite passes now: ``` Summary: 1334 tests passed 103 tests skipped 0 tests failed 0 tests not started (parent test skipped or failed) 0 unexpected errors 1437 tests considered ``` Signed-off-by: Edwin Török <[email protected]>

Reported by `-fsanitize=memory`: ``` > ==102752==WARNING: MemorySanitizer: use-of-uninitialized-value > #0 0x7f2ba7fb4ea4 in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:496:18 > #1 0x7f2ba7fbc016 in caml_ml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:1207:9 > ocaml#2 0x59ba5c in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 > ocaml#3 0x5a9220 in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 > ocaml#4 0x540d6b in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 > ocaml#5 0x7f2ba8120087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#6 0x7f2ba812014a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 617637580ee48eff08a2bce790e1667ad09f3b69) > > Uninitialized value was stored to memory at > #0 0x7f2ba7fb4e9d in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:497:69 > #1 0x7f2ba7fbc016 in caml_ml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:1207:9 > ocaml#2 0x59ba5c in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 > ocaml#3 0x5a9220 in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 > ocaml#4 0x540d6b in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 > ocaml#5 0x7f2ba8120087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#6 0x7f2ba812014a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 617637580ee48eff08a2bce790e1667ad09f3b69) > > Uninitialized value was created by an allocation of 'buf' in the stack frame > #0 0x7f2ba7fb3dbc in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:402:7 > ``` This is in fact an EV_LIFECYCLE with EV_RING_STOP, which has 0 additional data, and thus msg_length 2: ``` runtime/runtime_events.c: EV_RUNTIME, (ev_message_type){.runtime=EV_LIFECYCLE}, EV_RING_STOP, 0, ``` Attempting to read from `buf[2]` would read uninitialized data (or potentially beyond the end of the buffer). Check `msg_length` before reading. Signed-off-by: Edwin Török <[email protected]>

Bigarrays are printed in the toplevel as `<abstr>`, but ObjTbl.mem computes a hash. However bigarrays are uninitialized when allocated, so this seems to be a genuine bug: ``` ==133712==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x4e6d11 in caml_ba_hash /var/home/edwin/git/ocaml/runtime/bigarray.c:486:45 #1 0x52474a in caml_hash /var/home/edwin/git/ocaml/runtime/hash.c:251:35 ocaml#2 0x599ebf in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1065:14 ocaml#3 0x5a909a in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 ocaml#4 0x540ccb in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 ocaml#5 0x7f0910abb087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#6 0x7f0910abb14a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) Uninitialized value was created by a heap allocation #0 0x47d306 in malloc (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x47d306) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) #1 0x4e7960 in caml_ba_alloc /var/home/edwin/git/ocaml/runtime/bigarray.c:246:12 ocaml#2 0x4e801f in caml_ba_create /var/home/edwin/git/ocaml/runtime/bigarray.c:673:10 ocaml#3 0x59b8fc in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 ocaml#4 0x5a909a in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 ocaml#5 0x540ccb in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 ocaml#6 0x7f0910abb087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#7 0x7f0910abb14a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#8 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) SUMMARY: MemorySanitizer: use-of-uninitialized-value /var/home/edwin/git/ocaml/runtime/bigarray.c:486:45 in caml_ba_hash ``` The hashing is only needed to avoid recursion, skip it when the OCaml value doesn't contain further nested OCaml values, i.e. when it wouldn't be scanned by the GC. The testsuite passes now: ``` Summary: 1335 tests passed 102 tests skipped 0 tests failed 0 tests not started (parent test skipped or failed) 0 unexpected errors 1437 tests considered ``` Suggested-by: Gabriel Scherer <[email protected]> Signed-off-by: Edwin Török <[email protected]>

Found by -fsanitize=memory -fsanitize-memory-track-origins: ``` > ==102752==WARNING: MemorySanitizer: use-of-uninitialized-value > #0 0x7f2ba7fb4ea4 in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:496:18 > #1 0x7f2ba7fbc016 in caml_ml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:1207:9 > ocaml#2 0x59ba5c in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 > ocaml#3 0x5a9220 in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 > ocaml#4 0x540d6b in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 > ocaml#5 0x7f2ba8120087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#6 0x7f2ba812014a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 617637580ee48eff08a2bce790e1667ad09f3b69) > > Uninitialized value was stored to memory at > #0 0x7f2ba7fb4e9d in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:497:69 > #1 0x7f2ba7fbc016 in caml_ml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:1207:9 > ocaml#2 0x59ba5c in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 > ocaml#3 0x5a9220 in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 > ocaml#4 0x540d6b in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 > ocaml#5 0x7f2ba8120087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#6 0x7f2ba812014a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 617637580ee48eff08a2bce790e1667ad09f3b69) > > Uninitialized value was created by an allocation of 'buf' in the stack frame > #0 0x7f2ba7fb3dbc in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:402:7 > ``` This is in fact an EV_LIFECYCLE with EV_RING_STOP, which has 0 additional data, and thus msg_length 2: ``` runtime/runtime_events.c: EV_RUNTIME, (ev_message_type){.runtime=EV_LIFECYCLE}, EV_RING_STOP, 0, ``` Attempting to read from `buf[2]` would read uninitialized data. Signed-off-by: Edwin Török <[email protected]>

The toplevel printer detects cycles by keeping a hashtable of values that it has already traversed. However, some OCaml runtime types (at least bigarrays) may be partially uninitialized, and hashing them at arbitrary program points may read uninitialized memory. In particular, the OCaml testsuite fails when running with a memory-sanitizer enabled, as bigarray printing results in reads to uninitialized memory: ``` ==133712==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x4e6d11 in caml_ba_hash /var/home/edwin/git/ocaml/runtime/bigarray.c:486:45 #1 0x52474a in caml_hash /var/home/edwin/git/ocaml/runtime/hash.c:251:35 ocaml#2 0x599ebf in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1065:14 ocaml#3 0x5a909a in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 ocaml#4 0x540ccb in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 ocaml#5 0x7f0910abb087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#6 0x7f0910abb14a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) Uninitialized value was created by a heap allocation #0 0x47d306 in malloc (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x47d306) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) #1 0x4e7960 in caml_ba_alloc /var/home/edwin/git/ocaml/runtime/bigarray.c:246:12 ocaml#2 0x4e801f in caml_ba_create /var/home/edwin/git/ocaml/runtime/bigarray.c:673:10 ocaml#3 0x59b8fc in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 ocaml#4 0x5a909a in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 ocaml#5 0x540ccb in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 ocaml#6 0x7f0910abb087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#7 0x7f0910abb14a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) ocaml#8 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) SUMMARY: MemorySanitizer: use-of-uninitialized-value /var/home/edwin/git/ocaml/runtime/bigarray.c:486:45 in caml_ba_hash ``` The only use of hashing in genprintval is to avoid cycles, that is, it is only useful for OCaml values that contain other OCaml values (including possibly themselves). Bigarrays cannot introduce cycles, and they are always printed as "<abstr>" anyway. The present commit proposes to be more conservative in which values are hashed by the cycle detector to avoid this issue: we skip hashing any value with tag above No_scan_tag -- which may not contain any OCaml values. Suggested-by: Gabriel Scherer <[email protected]> Signed-off-by: Edwin Török <[email protected]>

Found by -fsanitize=memory -fsanitize-memory-track-origins: ``` > ==102752==WARNING: MemorySanitizer: use-of-uninitialized-value > #0 0x7f2ba7fb4ea4 in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:496:18 > #1 0x7f2ba7fbc016 in caml_ml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:1207:9 > ocaml#2 0x59ba5c in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 > ocaml#3 0x5a9220 in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 > ocaml#4 0x540d6b in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 > ocaml#5 0x7f2ba8120087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#6 0x7f2ba812014a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 617637580ee48eff08a2bce790e1667ad09f3b69) > > Uninitialized value was stored to memory at > #0 0x7f2ba7fb4e9d in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:497:69 > #1 0x7f2ba7fbc016 in caml_ml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:1207:9 > ocaml#2 0x59ba5c in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 > ocaml#3 0x5a9220 in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 > ocaml#4 0x540d6b in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 > ocaml#5 0x7f2ba8120087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#6 0x7f2ba812014a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) > ocaml#7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 617637580ee48eff08a2bce790e1667ad09f3b69) > > Uninitialized value was created by an allocation of 'buf' in the stack frame > #0 0x7f2ba7fb3dbc in caml_runtime_events_read_poll /var/home/edwin/git/ocaml/otherlibs/runtime_events/runtime_events_consumer.c:402:7 > ``` This is in fact an EV_LIFECYCLE with EV_RING_STOP, which has 0 additional data, and thus msg_length 2: ``` runtime/runtime_events.c: EV_RUNTIME, (ev_message_type){.runtime=EV_LIFECYCLE}, EV_RING_STOP, 0, ``` Attempting to read from `buf[2]` would read uninitialized data. Signed-off-by: Edwin Török <[email protected]>

The toplevel printer detects cycles by keeping a hashtable of values that it has already traversed. However, some OCaml runtime types (at least bigarrays) may be partially uninitialized, and hashing them at arbitrary program points may read uninitialized memory. In particular, the OCaml testsuite fails when running with a memory-sanitizer enabled, as bigarray printing results in reads to uninitialized memory: ``` ==133712==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x4e6d11 in caml_ba_hash /var/home/edwin/git/ocaml/runtime/bigarray.c:486:45 #1 0x52474a in caml_hash /var/home/edwin/git/ocaml/runtime/hash.c:251:35 #2 0x599ebf in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1065:14 #3 0x5a909a in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 #4 0x540ccb in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 #5 0x7f0910abb087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) #6 0x7f0910abb14a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) #7 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) Uninitialized value was created by a heap allocation #0 0x47d306 in malloc (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x47d306) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) #1 0x4e7960 in caml_ba_alloc /var/home/edwin/git/ocaml/runtime/bigarray.c:246:12 #2 0x4e801f in caml_ba_create /var/home/edwin/git/ocaml/runtime/bigarray.c:673:10 #3 0x59b8fc in caml_interprete /var/home/edwin/git/ocaml/runtime/interp.c:1058:14 #4 0x5a909a in caml_main /var/home/edwin/git/ocaml/runtime/startup_byt.c:575:9 #5 0x540ccb in main /var/home/edwin/git/ocaml/runtime/main.c:37:3 #6 0x7f0910abb087 in __libc_start_call_main (/lib64/libc.so.6+0x2a087) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) #7 0x7f0910abb14a in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2a14a) (BuildId: 8f53abaad945a669f2bdcd25f471d80e077568ef) #8 0x441804 in _start (/var/home/edwin/git/ocaml/runtime/ocamlrun+0x441804) (BuildId: 7a60eef57e1c2baf770bc38d10d6c227e60ead37) SUMMARY: MemorySanitizer: use-of-uninitialized-value /var/home/edwin/git/ocaml/runtime/bigarray.c:486:45 in caml_ba_hash ``` The only use of hashing in genprintval is to avoid cycles, that is, it is only useful for OCaml values that contain other OCaml values (including possibly themselves). Bigarrays cannot introduce cycles, and they are always printed as "<abstr>" anyway. The present commit proposes to be more conservative in which values are hashed by the cycle detector to avoid this issue: we skip hashing any value with tag above No_scan_tag -- which may not contain any OCaml values. Suggested-by: Gabriel Scherer <[email protected]> Signed-off-by: Edwin Török <[email protected]> Co-authored-by: Edwin Török <[email protected]>

Parse -.x**2. (unary -.) as -.(x**2.).

d009bae

This is what is expected mathematically. Note that -2.**2. is parsed as (-2.)**2. because -2. is considered to be a constant. However -.2.**2. is parsed as -.(2.**2.). Fix http://caml.inria.fr/mantis/view.php?id=3414

gasche closed this Dec 13, 2014

bactrian pushed a commit that referenced this pull request Apr 1, 2015

Cosmetic changes to decrease OCamlPro's patch #2

bc5ef95

git-svn-id: http://caml.inria.fr/svn/ocaml/version/4.02@15978 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

xavierleroy mentioned this pull request Aug 6, 2015

Compiling the run-time system at higher levels of C optimization #226

Merged

AltGr pushed a commit to AltGr/ocaml that referenced this pull request Oct 10, 2015

Merge pull request ocaml#2 from AltGr/comparison_branch

9d01ff1

Add Gc.print_stat hook to std_exit.ml

xavierleroy mentioned this pull request Mar 28, 2017

Remove ability to run OCaml code in a Unix signal handler #1107

Closed

damiendoligez added a commit that referenced this pull request Oct 27, 2017

Merge pull request #1444 from dra27/gpr1416-fixes

10b309f

Enable UTF-8 on Windows 10 Console (Mark #2)

gasche pushed a commit that referenced this pull request Oct 27, 2017

Merge pull request #1444 from dra27/gpr1416-fixes

7103830

Enable UTF-8 on Windows 10 Console (Mark #2) (cherry picked from commit 10b309f)

xavierleroy mentioned this pull request Jul 19, 2018

Add Filename.quote_command function #1492

Merged

jfehrle added a commit to jfehrle/ocaml that referenced this pull request Aug 4, 2020

Fix tests ocaml#2

af8e1c8

jfehrle added a commit to jfehrle/ocaml that referenced this pull request Aug 4, 2020

Fix tests ocaml#2

5d554df

jfehrle added a commit to jfehrle/ocaml that referenced this pull request Aug 5, 2020

Fix tests ocaml#2

95f2882

shindere added a commit that referenced this pull request Aug 11, 2020

Split the extra-checks job, take #2

541ade5

shindere added a commit that referenced this pull request Aug 14, 2020

Define Inria CI's other-configs job as a Jenkins pipeline, take #2

7b2689b

shindere added a commit that referenced this pull request Sep 17, 2020

Inria CI: use a timeout, take #2

ceb13a2

Let's try with a very short timeout, to make sure the job will exceed it.

shindere mentioned this pull request Feb 11, 2021

By default, use the C compiler driver rather than calling the assembler directly #10176

Merged

shindere mentioned this pull request Mar 11, 2022

GitHub Actions / ocamltest / testsuite / OCaml 5 #10980

Open

16 tasks

andreas-schwab mentioned this pull request Nov 28, 2022

ocamlopt.opt crashes from stack overflow while building coccinelle on RISC-V #11765

Closed

shindere mentioned this pull request Mar 1, 2023

Use a dedicated type to represent global identifiers in CMO files #12031

Merged

DMaroo added a commit to DMaroo/ocaml that referenced this pull request Dec 16, 2023

working change ocaml#2

66b25ea

EmileTrotignon pushed a commit to EmileTrotignon/ocaml that referenced this pull request Jan 12, 2024

Merge pull request ocaml#2 from patricoferris/add-tutorial

300f834

add a tutorial and a meeting

EmileTrotignon pushed a commit to EmileTrotignon/ocaml that referenced this pull request Jan 12, 2024

Merge pull request ocaml#2 from ocaml/cms/tutorials/introduction

74d1909

Automatically generated. Merged on Netlify CMS.

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Parse -.x2. (unary -.) as -.(x2.). Fix PR#3414 #2

Parse -.x2. (unary -.) as -.(x2.). Fix PR#3414 #2

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Parse -.x**2. (unary -.) as -.(x**2.). Fix PR#3414 #2

Parse -.x**2. (unary -.) as -.(x**2.). Fix PR#3414 #2

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Chris00 commented Aug 20, 2013

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Parse -.x2. (unary -.) as -.(x2.). Fix PR#3414 #2

Parse -.x2. (unary -.) as -.(x2.). Fix PR#3414 #2