[Bug libfortran/80365] undefined memcpy while writing zero length array on unformatted stream in unix.c

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80365

Thomas Koenig  changed:

   What|Removed |Added

 Status|ASSIGNED|RESOLVED
 Resolution|--- |FIXED

--- Comment #7 from Thomas Koenig  ---
From the lack of reaction, no interest in backporting.

Closing.

[Bug libfortran/80365] undefined memcpy while writing zero length array on unformatted stream in unix.c

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80365

--- Comment #6 from Thomas Koenig  ---
Forgot the PR in the commit message... here it is:

https://gcc.gnu.org/viewcvs?rev=250473=gcc=rev

[Bug libfortran/80365] undefined memcpy while writing zero length array on unformatted stream in unix.c

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80365

Thomas Koenig  changed:

   What|Removed |Added

 Status|NEW |ASSIGNED
   Assignee|unassigned at gcc dot gnu.org  |tkoenig at gcc dot 
gnu.org

--- Comment #5 from Thomas Koenig  ---
Looks straightforward... let's see.

[Bug libfortran/80365] undefined memcpy while writing zero length array on unformatted stream in unix.c

[zeccav at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80365

--- Comment #4 from Vittorio Zecca  ---
Or you may add

assert(buf);

just before the memcpy library call.

If nbyte==0 then it should be harmless, but undefined.

assert(buf || !nbyte) should catch an error situation

[Bug libfortran/80365] undefined memcpy while writing zero length array on unformatted stream in unix.c

[dominiq at lps dot ens.fr]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80365

--- Comment #3 from Dominique d'Humieres  ---
> How do I actually obtain this error?

I see it with a build configured with

Configured with: ../work/configure --prefix=/opt/gcc/gcc8g
--enable-languages=c,c++,fortran --with-gmp=/opt/mp-new --with-system-zlib
--with-isl=/opt/mp-new --disable-bootstrap --disable-multilib
--disable-libstdcxx CFLAGS='-L/opt/gcc/gcc7a/lib -lasan -lubsan
-fsanitize=address,undefined,leak -Og -g -fno-omit-frame-pointer'
CXXFLAGS='-fsanitize=address,undefined,leak -Og -g -fno-omit-frame-pointer'
LDFLAGS='-L/opt/gcc/gcc7a/lib -lasan -lubsan -ldl -lpthread'

../../../work/libgfortran/io/unix.c:597:7: runtime error: null pointer passed
as argument 2, which is declared to never be null

at run time.

[Bug libfortran/80365] undefined memcpy while writing zero length array on unformatted stream in unix.c

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80365

Thomas Koenig  changed:

   What|Removed |Added

 CC||tkoenig at gcc dot gnu.org

--- Comment #2 from Thomas Koenig  ---
How do I actually obtain this error?

[Bug libfortran/80365] undefined memcpy while writing zero length array on unformatted stream in unix.c

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80365

Martin Liška  changed:

   What|Removed |Added

 Status|UNCONFIRMED |NEW
   Last reconfirmed||2017-04-10
 CC||marxin at gcc dot gnu.org
 Ever confirmed|0   |1

--- Comment #1 from Martin Liška  ---
Confirmed.