In my experience, "-Wmaybe-uninitialized" is a great way to generate false positive compiler warnings and nothing else. Jeff On Thu, Apr 7, 2016 at 11:46 AM, Barry Smith <[email protected]> wrote:

src/sys/classes/bag/f2003-src/fsrc/bagenum.F has the code fragment

Subroutine PetscBagRegisterEnum(bag,addr,FArray,def,n,h,ierr) use,intrinsic :: iso_c_binding implicit none

PetscBag bag character(*) n,h character(*) FArray(*) PetscEnum :: def PetscErrorCode,intent(out) :: ierr PetscReal addr(*)

Type(C_Ptr),Dimension(:),Pointer :: CArray character(kind=c_char),pointer :: nullc => null() PetscInt :: i,Len Character(kind=C_char,len=256),Dimension(:),Pointer::list1

do i=1,256 if (len_trim(Farray(i)) .eq. 0) then Len = i-1 goto 100 endif if (len_trim(Farray(i)) .gt. 255) then ierr = PETSC_ERR_ARG_OUTOFRANGE return endif enddo ierr = PETSC_ERR_ARG_OUTOFRANGE return

100 continue

Allocate(list1(Len),stat=ierr); Allocate(CArray(Len+1),stat=ierr) do i=1,Len list1(i) = trim(FArray(i))//C_NULL_CHAR enddo

CArray = (/(c_loc(list1(i)),i=1,Len),c_loc(nullc)/) call PetscBagRegisterEnumPrivate(bag,addr,CArray,def,n,h,ierr) DeAllocate(CArray) DeAllocate(list1) End Subroutine

which produces the following warning with one Fortran compiler:

/Users/petsc/petsc.clone-4/src/sys/objects/f2003-src/fsrc/optionenum.F:35:0:

CArray = (/(c_loc(list1(i)),i=1,Len),c_loc(nullc)/) ^ Warning: 'list1.data' may be used uninitialized in this function [-Wmaybe-uninitialized]

Do any Fortran programmers know if the code is correct or if this is an incorrect warning from the compiler?

Thanks

Barry

-- Jeff Hammond [email protected] http://jeffhammond.github.io/