[gcc r13-8558] Fortran: error recovery on arithmetic overflow on unary operations [PR113799]

[Harald Anlauf via Gcc-cvs]

https://gcc.gnu.org/g:ec8303dea72ed4f9ae9fdf3c996a0deef6809351

commit r13-8558-gec8303dea72ed4f9ae9fdf3c996a0deef6809351
Author: Harald Anlauf <anl...@gmx.de>
Date:   Thu Feb 8 21:51:38 2024 +0100

    Fortran: error recovery on arithmetic overflow on unary operations 
[PR113799]
    
            PR fortran/113799
    
    gcc/fortran/ChangeLog:
    
            * arith.cc (reduce_unary): Remember any overflow encountered during
            reduction of unary arithmetic operations on array constructors and
            continue, and return error status, but terminate on serious errors.
    
    gcc/testsuite/ChangeLog:
    
            * gfortran.dg/arithmetic_overflow_2.f90: New test.
    
    (cherry picked from commit b3d622d70ba209b63471fc1b0970870046e55745)

Diff:
---
 gcc/fortran/arith.cc                                | 11 ++++++++---
 gcc/testsuite/gfortran.dg/arithmetic_overflow_2.f90 | 12 ++++++++++++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/gcc/fortran/arith.cc b/gcc/fortran/arith.cc
index fcf37d48bfc..5673c76823a 100644
--- a/gcc/fortran/arith.cc
+++ b/gcc/fortran/arith.cc
@@ -1323,6 +1323,7 @@ reduce_unary (arith (*eval) (gfc_expr *, gfc_expr **), 
gfc_expr *op,
   gfc_constructor *c;
   gfc_expr *r;
   arith rc;
+  bool ov = false;
 
   if (op->expr_type == EXPR_CONSTANT)
     return eval (op, result);
@@ -1336,13 +1337,17 @@ reduce_unary (arith (*eval) (gfc_expr *, gfc_expr **), 
gfc_expr *op,
     {
       rc = reduce_unary (eval, c->expr, &r);
 
-      if (rc != ARITH_OK)
+      /* Remember any overflow encountered during reduction and continue,
+        but terminate on serious errors.  */
+      if (rc == ARITH_OVERFLOW)
+       ov = true;
+      else if (rc != ARITH_OK)
        break;
 
       gfc_replace_expr (c->expr, r);
     }
 
-  if (rc != ARITH_OK)
+  if (rc != ARITH_OK && rc != ARITH_OVERFLOW)
     gfc_constructor_free (head);
   else
     {
@@ -1363,7 +1368,7 @@ reduce_unary (arith (*eval) (gfc_expr *, gfc_expr **), 
gfc_expr *op,
       *result = r;
     }
 
-  return rc;
+  return ov ? ARITH_OVERFLOW : rc;
 }
 
 
diff --git a/gcc/testsuite/gfortran.dg/arithmetic_overflow_2.f90 
b/gcc/testsuite/gfortran.dg/arithmetic_overflow_2.f90
new file mode 100644
index 00000000000..6ca27f74215
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/arithmetic_overflow_2.f90
@@ -0,0 +1,12 @@
+! { dg-do compile }
+! { dg-additional-options "-frange-check" }
+!
+! PR fortran/113799 - handle arithmetic overflow on unary minus
+
+program p
+  implicit none
+  real, parameter :: inf = real(z'7F800000')
+  real, parameter :: someInf(*) = [inf, 0.]
+  print *, -someInf         ! { dg-error "Arithmetic overflow" }
+  print *, minval(-someInf) ! { dg-error "Arithmetic overflow" }
+end