https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67541
Bug ID: 67541
Summary: -Wconversion-extra no warning on double = double +
single
Product: gcc
Version: 5.2.1
Status: UNCONFIRMED
Severity: minor
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: jamiebayne at hotmail dot com
Target Milestone: ---
It is my belief (or at least desire) that every assignment in the following
program should emit a warning with the -Wconversion{,-extra} flags (GCC
5.2.1):
PROGRAM conversion_test
INTEGER, PARAMETER :: sp = KIND(1.0)
INTEGER, PARAMETER :: dp = KIND(1.d0)
REAL(sp) :: single
REAL(dp) :: double
double = 4.0_sp ! -Wconversion-extra: Warning: Conversion from
! REAL(4) to REAL(8) at (1)
double = single ! -Wconversion-extra: Warning: Conversion from
! REAL(4) to REAL(8) at (1)
single = double ! -Wconversion: Warning: Possible change of
! value in conversion from REAL(8) to
! REAL(4) at (1)
! -Wconversion-extra: Warning: Conversion from
! REAL(8) to REAL(4)
single = double + single ! -Wconversion: Warning: Possible change
! of value in conversion from REAL(8)
! to REAL(4) at (1)
! -Wconversion-extra: Conversion from
! REAL(8) to REAL(4) at (1)
! no warnings
single = 7.0_dp
double = double + single
END PROGRAM conversion_test
Is this intended behaviour, or am I right in thinking that particularly the
double = double + single line should give a warning?
(For my purposes, I'm specifically interested in any expression which results
in a cvtss2sd on x86-64.)
