gfortran or tree-ssa bug?

[Steve Kargl]

On Sun, Apr 04, 2004 at 12:26:25PM -0700, Steve Kargl wrote:
> > 
> > This is PR14059
> > 
> 
> See the following patch.  I do not currently have a copyright
> assignment for GCC, but this patch probably falls under the
> "small patch without assignment category".  Note, I added a
> gfc_option.warn_underflow option, but did not include a patch
> for gcc/options to define -Wunderflow. 
> 
> kargl[249] ../../bin/gfortran -o b -static b.f90
> kargl[250] ./b
> x =     0.000000    
> y =  (   0.000000    ,   0.000000    )
> kargl[251] ../../bin/gfortran -o b -static -Wall b.f90
>  In file b.f90:5
> 
>    x = sqrt(9.125)**2 - 9.125                                  
>           1
> Warning: Arithmetic underflow at (1)
>  In file b.f90:6
> 
>    y = cabs(cexp((-2.5, 1.375))) - exp(5.0 / (-2.0))
>       1
> Warning: Arithmetic underflow at (1)
> 
> Changelog
> 
> * gfortran.h (struct gfc_option_t): Add gfc_option.warn_underflow.
> * options.c (gfc_init.options, gfc_handle_option): Use it.
> * arith.c (eval_intrinsic): Use it.
> * arith.c: typos in comments.

Nothing like replying to oneself.  New patch attached.

Changelog

* gfortran.h (struct gfc_option_t): Add gfc_option.warn_underflow.
* options.c (gfc_init.options, gfc_handle_option): Use it.
* lang.opt: define -Wunderflow
* arith.c (eval_intrinsic): Use it.
* arith.c, misc.c: typos in comments.

-- 
steve
-------------- next part --------------
Index: arith.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/fortran/Attic/arith.c,v
retrieving revision 1.1.2.4
diff -u -u -r1.1.2.4 arith.c
--- arith.c	24 Mar 2004 11:14:07 -0000	1.1.2.4
+++ arith.c	4 Apr 2004 21:51:44 -0000
@@ -1130,7 +1130,7 @@
 
 
 /* Make sure a constant numeric expression is within the range for
-   it's type and kind.  Note that there's also a gfc_check_range(),
+   its type and kind.  Note that there's also a gfc_check_range(),
    but that one deals with the intrinsic RANGE function.  */
 
 arith
@@ -2173,8 +2173,12 @@
 
   if (rc != ARITH_OK)
     {				/* Something went wrong */
-      gfc_error ("%s at %L", gfc_arith_error (rc), &op1->where);
-      return NULL;
+      if (rc != ARITH_UNDERFLOW) {
+        gfc_error ("%s at %L", gfc_arith_error (rc), &op1->where);
+        return NULL;
+      } else if (gfc_option.warn_underflow == 1)
+        gfc_warning ("%s at %L", gfc_arith_error (rc), &op1->where);
+      goto runtime;
     }
 
   gfc_free_expr (op1);
Index: gfortran.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/fortran/Attic/gfortran.h,v
retrieving revision 1.1.2.11
diff -u -u -r1.1.2.11 gfortran.h
--- gfortran.h	4 Apr 2004 15:33:41 -0000	1.1.2.11
+++ gfortran.h	4 Apr 2004 21:51:45 -0000
@@ -1220,6 +1220,7 @@
   int warn_implicit_interface;
   int warn_line_truncation;
   int warn_surprising;
+  int warn_underflow;
   int warn_unused_labels;
 
   int flag_dollar_ok;
Index: lang.opt
===================================================================
RCS file: /cvs/gcc/gcc/gcc/fortran/Attic/lang.opt,v
retrieving revision 1.1.2.8
diff -u -u -r1.1.2.8 lang.opt
--- lang.opt	4 Apr 2004 15:33:41 -0000	1.1.2.8
+++ lang.opt	4 Apr 2004 21:51:45 -0000
@@ -57,6 +57,10 @@
 F95
 Warn about \"suspicious\" constructs
 
+Wunderflow
+F95
+Warn about underflow of numeric constants
+
 Wunused-labels
 F95
 Warn when a label is unused
Index: misc.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/fortran/Attic/misc.c,v
retrieving revision 1.1.2.1
diff -u -u -r1.1.2.1 misc.c
--- misc.c	26 Jul 2003 16:27:46 -0000	1.1.2.1
+++ misc.c	4 Apr 2004 21:51:45 -0000
@@ -178,7 +178,7 @@
 }
 
 
-/* Return a string descibing the type and kind of a typespec.  Because
+/* Return a string describing the type and kind of a typespec.  Because
    we return alternating buffers, this subroutine can appear twice in
    the argument list of a single statement.  */
 
@@ -245,8 +245,8 @@
 }
 
 
-/* Given an mstring array and a string, returns the value of the tag
-   field.  Returns the final tag if no matches to the string are
+/* Given an mstring array and a string, return the value of the tag
+   field.  Return the final tag if no matches to the string are
    found.  */
 
 int
Index: options.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/fortran/Attic/options.c,v
retrieving revision 1.1.2.11
diff -u -u -r1.1.2.11 options.c
--- options.c	4 Apr 2004 15:33:41 -0000	1.1.2.11
+++ options.c	4 Apr 2004 21:51:46 -0000
@@ -56,6 +56,7 @@
   gfc_option.warn_implicit_interface = 0;
   gfc_option.warn_line_truncation = 0;
   gfc_option.warn_surprising = 0;
+  gfc_option.warn_underflow = 0;
   gfc_option.warn_unused_labels = 0;
 
   gfc_option.flag_dollar_ok = 0;
@@ -123,6 +124,7 @@
   gfc_option.warn_aliasing = 1;
   gfc_option.warn_line_truncation = 1;
   gfc_option.warn_surprising = 1;
+  gfc_option.warn_underflow = 1;
   gfc_option.warn_unused_labels = 1;
 
   set_Wunused (1);
@@ -199,6 +201,10 @@
 
     case OPT_Wsurprising:
       gfc_option.warn_surprising = value;
+      break;
+
+    case OPT_Wunderflow:
+      gfc_option.warn_underflow = value;
       break;
 
     case OPT_Wunused_labels: