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From: "jvdelisle at charter dot net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libfortran/97017] New: The function determine_precision is
 called twice for each formatted real write
Date: Fri, 11 Sep 2020 03:13:30 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D97017

            Bug ID: 97017
           Summary: The function determine_precision is called twice for
                    each formatted real write
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libfortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jvdelisle at charter dot net
  Target Milestone: ---

I discovered this while working on the EX formattting feature. The
determine_precision function is called by both get_precision and inside the
macro FORMAT_FLOAT used by get_float_string.

To me this implies we have something factored wrong as we should not have to
call it twice to get things done. (a small performance issue as well as
obscure)

A simple test case will show the issue in a debugger:

! pr93727 EX Format Specifiers

program main
  implicit none
  real(4) :: r4
  real(8) :: r8
  r4 =3D 3.14158_4
  r8 =3D 12.3456789_8
  print *, r4, r8
end program main=