http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47085
janus at gcc dot gnu.org changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2010.12.29 22:39:46 Ever Confirmed|0 |1 --- Comment #1 from janus at gcc dot gnu.org 2010-12-29 22:39:46 UTC --- I have reduced the test case quite a bit, while maintaining the valgrind error: program ppde implicit none type :: t0 end type type, extends(t0) :: t1 integer, allocatable :: c(:) end type class(t0), allocatable :: x, y allocate(t1 :: x) allocate(y, source=x) end When compiling this with -g and running under valgrind, I get: ==26472== Conditional jump or move depends on uninitialised value(s) ==26472== at 0x4009B7: __copy_ppde_t1.1550 (ppde.f90:1) ==26472== by 0x400AD1: MAIN__ (ppde.f90:16) ==26472== by 0x400B74: main (ppde.f90:16) This means the error happens inside the copying routine of the extended type, and seems to be related to the allocatable component. In the original test case the error message appeared in a triple, because three allocatable components were involved. This is the same issue as described in PR 46408.