[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Sergey Fedorov changed: What|Removed |Added CC||vital.had at gmail dot com --- Comment #20 from Sergey Fedorov --- I just got the same error when building OpenCoarrays on 10.6.8 for ppc32: /opt/local/var/macports/build/_opt_PPCRosettaPorts_science_OpenCoarrays/OpenCoarrays/work/OpenCoarrays-2.10.0/src/tests/integration/pde_solvers/coarrayBurgers/main.F90:3:20: 3 | use, intrinsic :: ieee_arithmetic, only : ieee_is_nan |1 Fatal Error: Cannot find an intrinsic module named 'ieee_arithmetic' at (1) compilation terminated. Error: command: `/opt/local/bin/mpif90-mpich-gcc12 -I/opt/local/var/macports/build/_opt_PPCRosettaPorts_science_OpenCoarrays/OpenCoarrays/work/build/include/OpenCoarrays-2.10.0_GNU-12.2.0 -fcoarray=lib -DGCC_GE_7 -DGCC_GE_8 -DHAVE_MPI -DMPI_WORKING_MODULE -DPREFIX_NAME=_gfortran_caf_ -I/opt/local/var/macports/build/_opt_PPCRosettaPorts_science_OpenCoarrays/OpenCoarrays/work/build/src/tests/integration/pde_solvers/coarrayBurgers/library -pipe -Os -m32 -mmacosx-version-min=10.6 -c /opt/local/var/macports/build/_opt_PPCRosettaPorts_science_OpenCoarrays/OpenCoarrays/work/OpenCoarrays-2.10.0/src/tests/integration/pde_solvers/coarrayBurgers/main.F90 -o CMakeFiles/coarray_burgers_pde.dir/main.F90.o` failed to compile.
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 --- Comment #18 from Thomas Schwinge --- Author: tschwinge Date: Thu Mar 21 18:57:39 2019 New Revision: 269846 URL: https://gcc.gnu.org/viewcvs?rev=269846=gcc=rev Log: [testsuite, Fortran] Consistently set 'DEFAULT_FFLAGS' In the same 'runtest' instance, 'global' variables persist from one '*.exp' file to another. All other '*.exp' files are using " -pedantic-errors" instead of the empty string as the default for 'DEFAULT_FFLAGS'. Thus this setting of 'DEFAULT_FFLAGS' is not idempotent, depends on whether 'gfortran.dg/ieee/ieee.exp', or an other defining '*.exp' file is executed first. gcc/testsuite/ PR fortran/29383 * gfortran.dg/ieee/ieee.exp (DEFAULT_FFLAGS): Set the same as in other '*.exp' files. trunk r269845 Modified: branches/gcc-8-branch/gcc/testsuite/ChangeLog branches/gcc-8-branch/gcc/testsuite/gfortran.dg/ieee/ieee.exp
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 --- Comment #19 from Thomas Schwinge --- Author: tschwinge Date: Thu Mar 21 18:57:56 2019 New Revision: 269847 URL: https://gcc.gnu.org/viewcvs?rev=269847=gcc=rev Log: [testsuite, Fortran] Consistently set 'DEFAULT_FFLAGS' In the same 'runtest' instance, 'global' variables persist from one '*.exp' file to another. All other '*.exp' files are using " -pedantic-errors" instead of the empty string as the default for 'DEFAULT_FFLAGS'. Thus this setting of 'DEFAULT_FFLAGS' is not idempotent, depends on whether 'gfortran.dg/ieee/ieee.exp', or an other defining '*.exp' file is executed first. gcc/testsuite/ PR fortran/29383 * gfortran.dg/ieee/ieee.exp (DEFAULT_FFLAGS): Set the same as in other '*.exp' files. trunk r269845 Modified: branches/gcc-7-branch/gcc/testsuite/ChangeLog branches/gcc-7-branch/gcc/testsuite/gfortran.dg/ieee/ieee.exp
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 --- Comment #17 from Thomas Schwinge --- Author: tschwinge Date: Thu Mar 21 18:54:50 2019 New Revision: 269845 URL: https://gcc.gnu.org/viewcvs?rev=269845=gcc=rev Log: [testsuite, Fortran] Consistently set 'DEFAULT_FFLAGS' In the same 'runtest' instance, 'global' variables persist from one '*.exp' file to another. All other '*.exp' files are using " -pedantic-errors" instead of the empty string as the default for 'DEFAULT_FFLAGS'. Thus this setting of 'DEFAULT_FFLAGS' is not idempotent, depends on whether 'gfortran.dg/ieee/ieee.exp', or an other defining '*.exp' file is executed first. gcc/testsuite/ PR fortran/29383 * gfortran.dg/ieee/ieee.exp (DEFAULT_FFLAGS): Set the same as in other '*.exp' files. Modified: trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gfortran.dg/ieee/ieee.exp
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 --- Comment #15 from Francois-Xavier Coudert fxcoudert at gcc dot gnu.org --- Author: fxcoudert Date: Sat Jun 28 14:17:41 2014 New Revision: 212102 URL: https://gcc.gnu.org/viewcvs?rev=212102root=gccview=rev Log: PR fortran/29383 gcc/fortran/ * gfortran.h (gfc_simplify_ieee_selected_real_kind): New prototype. * libgfortran.h (GFC_FPE_*): Use simple integer values, valid in both C and Fortran. * expr.c (gfc_check_init_expr): Simplify IEEE_SELECTED_REAL_KIND. * simplify.c (gfc_simplify_ieee_selected_real_kind): New function. * module.c (mio_symbol): Keep track of symbols which came from intrinsic modules. (gfc_use_module): Keep track of the IEEE modules. * trans-decl.c (gfc_get_symbol_decl): Adjust code since we have new intrinsic modules. (gfc_build_builtin_function_decls): Build decls for ieee_procedure_entry and ieee_procedure_exit. (is_from_ieee_module, is_ieee_module_used, save_fp_state, restore_fp_state): New functions. (gfc_generate_function_code): Save and restore floating-point state on procedure entry/exit, when IEEE modules are used. * intrinsic.texi: Document the IEEE modules. libgfortran/ * configure.host: Add checks for IEEE support, rework priorities. * configure.ac: Define IEEE_SUPPORT, check for fpsetsticky and fpresetsticky. * configure: Regenerate. * Makefile.am: Build new ieee files, install IEEE_* modules. * Makefile.in: Regenerate. * gfortran.map (GFORTRAN_1.6): Add new symbols. * libgfortran.h (get_fpu_trap_exceptions, set_fpu_trap_exceptions, support_fpu_trap, set_fpu_except_flags, support_fpu_flag, support_fpu_rounding_mode, get_fpu_state, set_fpu_state): New prototypes. * config/fpu-*.h (get_fpu_trap_exceptions, set_fpu_trap_exceptions, support_fpu_trap, set_fpu_except_flags, support_fpu_flag, support_fpu_rounding_mode, get_fpu_state, set_fpu_state): New functions. * ieee/ieee_features.F90: New file. * ieee/ieee_exceptions.F90: New file. * ieee/ieee_arithmetic.F90: New file. * ieee/ieee_helper.c: New file. gcc/testsuite/ * lib/target-supports.exp (check_effective_target_fortran_ieee): New function. * gfortran.dg/ieee/ieee.exp: New file. * gfortran.dg/ieee/ieee_1.F90: New file. * gfortran.dg/ieee/ieee_2.f90: New file. * gfortran.dg/ieee/ieee_3.f90: New file. * gfortran.dg/ieee/ieee_4.f90: New file. * gfortran.dg/ieee/ieee_5.f90: New file. * gfortran.dg/ieee/ieee_6.f90: New file. * gfortran.dg/ieee/ieee_7.f90: New file. * gfortran.dg/ieee/ieee_rounding_1.f90: New file. Added: trunk/gcc/testsuite/gfortran.dg/ieee/ trunk/gcc/testsuite/gfortran.dg/ieee/ieee.exp trunk/gcc/testsuite/gfortran.dg/ieee/ieee_1.F90 trunk/gcc/testsuite/gfortran.dg/ieee/ieee_2.f90 trunk/gcc/testsuite/gfortran.dg/ieee/ieee_3.f90 trunk/gcc/testsuite/gfortran.dg/ieee/ieee_4.f90 trunk/gcc/testsuite/gfortran.dg/ieee/ieee_5.f90 trunk/gcc/testsuite/gfortran.dg/ieee/ieee_6.f90 trunk/gcc/testsuite/gfortran.dg/ieee/ieee_7.f90 trunk/gcc/testsuite/gfortran.dg/ieee/ieee_rounding_1.f90 trunk/libgfortran/ieee/ trunk/libgfortran/ieee/ieee_arithmetic.F90 trunk/libgfortran/ieee/ieee_exceptions.F90 trunk/libgfortran/ieee/ieee_features.F90 trunk/libgfortran/ieee/ieee_helper.c Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/expr.c trunk/gcc/fortran/gfortran.h trunk/gcc/fortran/intrinsic.texi trunk/gcc/fortran/libgfortran.h trunk/gcc/fortran/module.c trunk/gcc/fortran/simplify.c trunk/gcc/fortran/trans-decl.c trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/lib/target-supports.exp trunk/libgfortran/ChangeLog trunk/libgfortran/Makefile.am trunk/libgfortran/Makefile.in trunk/libgfortran/config/fpu-387.h trunk/libgfortran/config/fpu-aix.h trunk/libgfortran/config/fpu-generic.h trunk/libgfortran/config/fpu-glibc.h trunk/libgfortran/config/fpu-sysv.h trunk/libgfortran/configure trunk/libgfortran/configure.ac trunk/libgfortran/configure.host trunk/libgfortran/gfortran.map trunk/libgfortran/libgfortran.h
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Francois-Xavier Coudert fxcoudert at gcc dot gnu.org changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution|--- |FIXED Target Milestone|--- |4.10.0 --- Comment #16 from Francois-Xavier Coudert fxcoudert at gcc dot gnu.org --- This has now been fixed on trunk (4.10). Hurray!
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Francois-Xavier Coudert fxcoudert at gcc dot gnu.org changed: What|Removed |Added Keywords||patch Status|NEW |ASSIGNED Assignee|unassigned at gcc dot gnu.org |fxcoudert at gcc dot gnu.org
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Francois-Xavier Coudert fxcoudert at gcc dot gnu.org changed: What|Removed |Added CC||fkrogh#gcc at mathalacarte dot com --- Comment #13 from Francois-Xavier Coudert fxcoudert at gcc dot gnu.org --- *** Bug 58020 has been marked as a duplicate of this bug. ***
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Bug 29383 depends on bug 58020, which changed state. Bug 58020 Summary: Code for handling IEEE exceptions https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58020 What|Removed |Added Status|NEW |RESOLVED Resolution|--- |DUPLICATE
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Bug 29383 depends on bug 59026, which changed state. Bug 59026 Summary: ELEMENTAL procedure with VALUE arguments emits wrong code https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59026 What|Removed |Added Status|NEW |RESOLVED Resolution|--- |FIXED
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Francois-Xavier Coudert fxcoudert at gcc dot gnu.org changed: What|Removed |Added CC||fxcoudert at gcc dot gnu.org --- Comment #14 from Francois-Xavier Coudert fxcoudert at gcc dot gnu.org --- I posted a patch adding a rather complete IEEE support here: https://gcc.gnu.org/ml/fortran/2014-06/msg00038.html
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Walter Spector w6ws at earthlink dot net changed: What|Removed |Added CC||w6ws at earthlink dot net --- Comment #12 from Walter Spector w6ws at earthlink dot net --- Adding myself to the CC list, sympathizing with comment #5. Just IEEE_ARITHMETIC intrinsic functions for basic setting (e.g., IEEE_VALUE) and testing (e.g., IEEE_IS_NAN) with the default rounding mode, roughly equivalent to what g95 supports, would be very useful. I don't need fancy rounding modes.
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Bug 29383 depends on bug 59023, which changed state. Bug 59023 Summary: [4.9 regression] ICE in gfc_search_interface with BIND(C) http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59023 What|Removed |Added Status|ASSIGNED|RESOLVED Resolution|--- |FIXED
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 --- Comment #11 from Sean Santos quantheory at gmail dot com 2013-04-14 20:08:59 UTC --- I'm doing a bit of research because I'm considering trying to tackle part of this soon. I believe that the Fortran standard does not require the rounding mode to apply to operations performed during constant folding, so point 4 above is moot. Please see the collected interpretations of F2003: http://j3-fortran.org/doc/standing/links/016.txt Particularly see F03/0040 and F03/0078. In combination they guarantee that the compiler is allowed to transform expressions at compile time according to the mathematical equivalence rule regardless of the rounding mode. In any case, the rounding mode cannot always be established at compile time; if the committee had not decided upon this behavior, then constant folding would often be impossible, period. The Fortran 2003 and 2008 standards also give examples where constant folding and propagation are allowed to influence whether or not an IEEE exception is signaled.
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Sean Santos quantheory at gmail dot com changed: What|Removed |Added CC||quantheory at gmail dot com --- Comment #10 from Sean Santos quantheory at gmail dot com 2012-12-04 19:28:19 UTC --- Comment 9 seems a bit too pessimistic to me. For one, returning .false. for ieee_supports_* doesn't seem like a sidestep, but more like the correct behavior in an environment that lacks IEEE support (maybe even if the only reason is because the compiler has not implemented it). For another, as noted above, one important use of the ieee_arithmetic module is to test for NaN/Inf in a standard-conforming way, rather than using compiler-specific extensions. (AFAIK, gfortran is the only F2003 compiler that forces you to use a non-portable extension to do this.) For that functionality, the only likely problem I can see is in deciding when e.g. ieee_support_nan should return .true.. Of course this is only a fraction of what needs to be done (presumably the easiest part), but it's much better than nothing, particularly to address what I would expect to be one of the most common uses of this module.
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 --- Comment #8 from Andy Nelson andy.nelson at lanl dot gov 2012-10-09 15:19:36 UTC --- Interesting. Didn't see this dup originally in my search. In response to your other email (that it is very very hard), can you explain a bit why if you've got the time/inclination? My first thought was that it would be a fairly simple pass through/reimplementation of the fpclassify functionality of c. Thanks, Andy Nelson On Oct 6, 2012, at 6:08 PM, kargl at gcc dot gnu.org wrote: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 kargl at gcc dot gnu.org changed: What|Removed |Added CC||andy.nelson at lanl dot gov --- Comment #7 from kargl at gcc dot gnu.org 2012-10-07 00:08:49 UTC --- *** Bug 54840 has been marked as a duplicate of this bug. *** -- Configure bugmail: http://gcc.gnu.org/bugzilla/userprefs.cgi?tab=email --- You are receiving this mail because: --- You are on the CC list for the bug.
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 kargl at gcc dot gnu.org changed: What|Removed |Added CC||kargl at gcc dot gnu.org --- Comment #9 from kargl at gcc dot gnu.org 2012-10-09 17:00:42 UTC --- (In reply to comment #8) In response to your other email (that it is very very hard), can you explain a bit why if you've got the time/inclination? My first thought was that it would be a fairly simple pass through/reimplementation of the fpclassify functionality of c. There are a few reason (and this is just my opinion). 1) gcc runs on numerous cpu architectures (i386, x86_64, arm, sparc, powerpc, etc). Some (many? all?) do not have hardware support for IEEE754. An implementation needs to be able to work on most (all?) of these cpus. 2) gcc runs on numerous operating systems. The operating systems may or may not have sufficient support to allow an efficient IEEE754 implementation (a software implementation of IEEE754 will be slow). 3) Using C interoperability to access the fenv.h facility seems appealing, but gcc would need to deal with systems that do not have fenv.h. 4) gcc performs constant folding with mpfr, and in gfortran this constant folding is performed in round-to-nearest mode. gfortran would need to be update to delay constant folding until the rounding mode has been established. program foo use ieee_arithmetic real x call ieee_set_rounding_mode(ieee_down) x = 0.3 + 0.1999 ! Should be down in round-down? print '(Z0)', x end program foo 5) Finally, for some intrinsic functions, it is not possible to map to a libm routine without now putting a wrapper around the libm routine. For example, consider FRACTION(). The standard states: Result Value. The result has the value X*b**(-e), where b and e are as defined in 13.4 for the model representation of X. If X has the value zero, the result has the value zero. If X is an IEEE infinity, the result is that infinity. If X is an IEEE NaN, the result is that NaN. The word that in the result is that NaN is problematic. There are something like 2**p bit patterns that much NaN. Unfortunately, mapping FRACTION to libm's frexp gives the wrong NaN. See PR 48979 for a longer explanation. One can side step 1), 2), and 3) by unilaterally returning false for ieee_support_standard(), which of course indicates that the IEEE754 isn't standard. 4) and 5) are much harder to fix. Of course, I could be wrong.
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 kargl at gcc dot gnu.org changed: What|Removed |Added CC||andy.nelson at lanl dot gov --- Comment #7 from kargl at gcc dot gnu.org 2012-10-07 00:08:49 UTC --- *** Bug 54840 has been marked as a duplicate of this bug. ***
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Bill Long longb at cray dot com changed: What|Removed |Added CC||longb at cray dot com --- Comment #6 from Bill Long longb at cray dot com 2011-07-22 17:53:49 UTC --- Since most other compilers support ieee_arithmetic now, the lack of support in gfortran is becoming a portability issue. Simple test case with 4.6.1: cat t1.f90 program test use,intrinsic :: ieee_arithmetic real :: x read *, x if (ieee_is_nan(x)) then print *, Nan else print *, Not NaN end if end program test gfortran t1.f90 t1.f90:2.35: use,intrinsic :: ieee_arithmetic 1 Fatal Error: Can't find an intrinsic module named 'ieee_arithmetic' at (1)
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383 Thomas thenlich at users dot sourceforge.net changed: What|Removed |Added CC||thenlich at users dot ||sourceforge.net --- Comment #5 from Thomas thenlich at users dot sourceforge.net 2011-01-24 08:53:10 UTC --- Even a partial, incomplete support of module IEEE_ARITHMETIC would be very useful and much appreciated: From http://gcc.gnu.org/ml/gcc/2008-11/msg00372.html a) To set an IEEE value (NaN, INF, etc.) b) Check whether a value is NaN, etc. and IEEE_VALUE(X, IEEE_QUIET_NAN) So we wouldn't have to resort to non-standard functions like ISNAN() (http://gcc.gnu.org/onlinedocs/gfortran/ISNAN.html) anymore.
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
--- Comment #4 from burnus at gcc dot gnu dot org 2010-06-12 12:15 --- Malcolm Cohen wrote in Implementing the Standards..., http://www.fortran.bcs.org/2007/jubilee/f50.pdf, the following: IEEE module implementation Only if IEEE_GET_FLAG is directly called in a routine: save then clear the flags on entry, merge the flags on exit. Only in a routine that uses a mode setting procedure: save mode on entry, restore mode on exit. Parallelism and other optimisations are little impeded by the use of IEEE facilities (all IEEE semantics being local). -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
--- Comment #3 from burnus at gcc dot gnu dot org 2010-04-14 06:33 --- Some underflow module for Fortran: http://gcc.gnu.org/ml/fortran/2010-04/msg00144.html -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
--- Comment #2 from burnus at gcc dot gnu dot org 2009-09-07 08:07 --- Add links to some discussions to make sure it won't get lost: http://gcc.gnu.org/ml/gcc/2008-11/msg00372.html http://groups.google.com/group/comp.lang.fortran/browse_thread/thread/1efc9e7a19651b81 The thread which is here and maybe also some other fort...@gcc emails by Tim and Nick around this time: http://gcc.gnu.org/ml/fortran/2009-08/msg00338.html -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383
[Bug fortran/29383] Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support
--- Comment #1 from fxcoudert at gcc dot gnu dot org 2006-10-22 07:19 --- Confirmed. This one will probably be implemented after ISO_C_BINDING. -- fxcoudert at gcc dot gnu dot org changed: What|Removed |Added CC||fxcoudert at gcc dot gnu dot ||org Status|UNCONFIRMED |NEW Ever Confirmed|0 |1 Last reconfirmed|-00-00 00:00:00 |2006-10-22 07:19:52 date|| http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29383
