[gcc r14-6970] Fortran: bogus warnings with REPEAT intrinsic and -Wconversion-extra [PR96724]

[Harald Anlauf]

https://gcc.gnu.org/g:723bd722d616bbb427264930986f080d89207caa

commit r14-6970-g723bd722d616bbb427264930986f080d89207caa
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Fri Jan 5 23:38:56 2024 +0100

    Fortran: bogus warnings with REPEAT intrinsic and -Wconversion-extra [PR96724]
    
    gcc/fortran/ChangeLog:
    
            PR fortran/96724
            * iresolve.cc (gfc_resolve_repeat): Force conversion to
            gfc_charlen_int_kind before call to gfc_multiply.
    
    gcc/testsuite/ChangeLog:
    
            PR fortran/96724
            * gfortran.dg/repeat_8.f90: New test.
    
    Co-authored-by: José Rui Faustino de Sousa <jrfsousa@gmail.com>

Diff:
---
 gcc/fortran/iresolve.cc                |  10 ++-
 gcc/testsuite/gfortran.dg/repeat_8.f90 | 123 +++++++++++++++++++++++++++++++++
 2 files changed, 132 insertions(+), 1 deletion(-)

diff --git a/gcc/fortran/iresolve.cc b/gcc/fortran/iresolve.cc
index 5bb0bbc477b..c961cdbc2df 100644
--- a/gcc/fortran/iresolve.cc
+++ b/gcc/fortran/iresolve.cc
@@ -2363,7 +2363,15 @@ gfc_resolve_repeat (gfc_expr *f, gfc_expr *string,
     }
 
   if (tmp)
-    f->ts.u.cl->length = gfc_multiply (tmp, gfc_copy_expr (ncopies));
+    {
+      /* Force-convert to gfc_charlen_int_kind before gfc_multiply.  */
+      gfc_expr *e = gfc_copy_expr (ncopies);
+      gfc_typespec ts = tmp->ts;
+      ts.kind = gfc_charlen_int_kind;
+      gfc_convert_type_warn (e, &ts, 2, 0);
+      gfc_convert_type_warn (tmp, &ts, 2, 0);
+      f->ts.u.cl->length = gfc_multiply (tmp, e);
+    }
 }
 
 
diff --git a/gcc/testsuite/gfortran.dg/repeat_8.f90 b/gcc/testsuite/gfortran.dg/repeat_8.f90
new file mode 100644
index 00000000000..9dd379ac96b
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/repeat_8.f90
@@ -0,0 +1,123 @@
+! { dg-do compile }
+! { dg-additional-options "-Wconversion-extra" }
+!
+! Test fix for PR fortran/96724
+!
+! Contributed by José Rui Faustino de Sousa 
+
+program repeat_p
+  use, intrinsic :: iso_fortran_env, only: int8, int16, int32, int64
+  implicit none
+
+  integer, parameter :: n = 20
+  integer, parameter :: ucs4 = selected_char_kind ('ISO_10646')
+
+  integer(kind=int8),  parameter :: p08 = int(n, kind=int8)
+  integer(kind=int16), parameter :: p16 = int(n, kind=int16)
+  integer(kind=int16), parameter :: p32 = int(n, kind=int32)
+  integer(kind=int16), parameter :: p64 = int(n, kind=int64)
+
+  integer(kind=int8)  :: i08
+  integer(kind=int16) :: i16
+  integer(kind=int32) :: i32
+  integer(kind=int64) :: i64
+
+  character(len=n,kind=1)    :: c
+  character(len=n,kind=ucs4) :: d
+
+  i08 = p08
+  c = repeat('X', 20_int8)
+  c = repeat('X', i08)
+  c = repeat('X', p08)
+  c = repeat('X', len08(c))
+  d = repeat(ucs4_'X', 20_int8)
+  d = repeat(ucs4_'X', i08)
+  d = repeat(ucs4_'X', p08)
+  d = repeat(ucs4_'X', len08(c))
+  i16 = p16
+  c = repeat('X', 20_int16)
+  c = repeat('X', i16)
+  c = repeat('X', p16)
+  c = repeat('X', len16(c))
+  d = repeat(ucs4_'X', 20_int16)
+  d = repeat(ucs4_'X', i16)
+  d = repeat(ucs4_'X', p16)
+  d = repeat(ucs4_'X', len16(c))
+  i32 = p32
+  c = repeat('X', 20_int32)
+  c = repeat('X', i32)
+  c = repeat('X', p32)
+  c = repeat('X', len32(c))
+  d = repeat(ucs4_'X', 20_int32)
+  d = repeat(ucs4_'X', i32)
+  d = repeat(ucs4_'X', p32)
+  d = repeat(ucs4_'X', len32(c))
+  i64 = p64
+  c = repeat('X', 20_int64)
+  c = repeat('X', i64)
+  c = repeat('X', p64)
+  c = repeat('X', len64(c))
+  d = repeat(ucs4_'X', 20_int64)
+  d = repeat(ucs4_'X', i64)
+  d = repeat(ucs4_'X', p64)
+  d = repeat(ucs4_'X', len64(c))
+
+contains
+
+  function len08(x) result(l)
+    character(len=*), intent(in) :: x
+    integer(kind=int8) :: l
+
+    l = int(len(x), kind=int8)
+  end function len08
+
+  function len16(x) result(l)
+    character(len=*), intent(in) :: x
+    integer(kind=int16) :: l
+
+    l = int(len(x), kind=int16)
+  end function len16
+
+  function len32(x) result(l)
+    character(len=*), intent(in) :: x
+    integer(kind=int32) :: l
+
+    l = int(len(x), kind=int32)
+  end function len32
+
+  function len64(x) result(l)
+    character(len=*), intent(in) :: x
+    integer(kind=int64) :: l
+
+    l = int(len(x), kind=int64)
+  end function len64
+
+  function ulen08(x) result(l)
+    character(len=*,kind=ucs4), intent(in) :: x
+    integer(kind=int8) :: l
+
+    l = int(len(x), kind=int8)
+  end function ulen08
+
+  function ulen16(x) result(l)
+    character(len=*,kind=ucs4), intent(in) :: x
+    integer(kind=int16) :: l
+
+    l = int(len(x), kind=int16)
+  end function ulen16
+
+  function ulen32(x) result(l)
+    character(len=*,kind=ucs4), intent(in) :: x
+    integer(kind=int32) :: l
+
+    l = int(len(x), kind=int32)
+  end function ulen32
+
+  function ulen64(x) result(l)
+    character(len=*,kind=ucs4), intent(in) :: x
+    integer(kind=int64) :: l
+
+    l = int(len(x), kind=int64)
+  end function ulen64
+
+end program repeat_p