Prevent csrscl/zdrscl from going to infinite loop on Infinity input

michael-chuvelev · michael-chuvelev · commit 3c9f92b3918a · 2025-09-19T09:24:38.000-07:00
diff --git a/SRC/csrscl.f b/SRC/csrscl.f
@@ -112,13 +112,19 @@ SUBROUTINE CSRSCL( N, SA, SX, INCX )
 *     ..
 *     .. Intrinsic Functions ..
       INTRINSIC          ABS
+      INTRINSIC          HUGE
 *     ..
 *     .. Executable Statements ..
 *
 *     Quick return if possible
 *
       IF( N.LE.0 )
      $   RETURN
+*
+      IF( SA.GT.HUGE(SA) .OR. SA.LT.-HUGE(SA) ) THEN
+         CALL CSSCAL( N, SA, SX, INCX )
+         RETURN
+      END IF
 *
 *     Get machine parameters
 *
diff --git a/SRC/zdrscl.f b/SRC/zdrscl.f
@@ -112,13 +112,19 @@ SUBROUTINE ZDRSCL( N, SA, SX, INCX )
 *     ..
 *     .. Intrinsic Functions ..
       INTRINSIC          ABS
+      INTRINSIC          HUGE
 *     ..
 *     .. Executable Statements ..
 *
 *     Quick return if possible
 *
       IF( N.LE.0 )
      $   RETURN
+*
+      IF( SA.GT.HUGE(SA) .OR. SA.LT.-HUGE(SA) ) THEN
+         CALL ZDSCAL( N, SA, SX, INCX )
+         RETURN
+      END IF
 *
 *     Get machine parameters
 *

Original file line number	Diff line number	Diff line change
`@@ -112,13 +112,19 @@ SUBROUTINE CSRSCL( N, SA, SX, INCX )`
`112`	`112`	`* ..`
`113`	`113`	`* .. Intrinsic Functions ..`
`114`	`114`	`INTRINSIC ABS`
	`115`	`+ INTRINSIC HUGE`
`115`	`116`	`* ..`
`116`	`117`	`* .. Executable Statements ..`
`117`	`118`	`*`
`118`	`119`	`* Quick return if possible`
`119`	`120`	`*`
`120`	`121`	`IF( N.LE.0 )`
`121`	`122`	`$ RETURN`
	`123`	`+*`
	`124`	`+ IF( SA.GT.HUGE(SA) .OR. SA.LT.-HUGE(SA) ) THEN`
	`125`	`+ CALL CSSCAL( N, SA, SX, INCX )`
	`126`	`+ RETURN`
	`127`	`+ END IF`
`122`	`128`	`*`
`123`	`129`	`* Get machine parameters`
`124`	`130`	`*`
Original file line number	Diff line number	Diff line change
`@@ -112,13 +112,19 @@ SUBROUTINE ZDRSCL( N, SA, SX, INCX )`
`112`	`112`	`* ..`
`113`	`113`	`* .. Intrinsic Functions ..`
`114`	`114`	`INTRINSIC ABS`
	`115`	`+ INTRINSIC HUGE`
`115`	`116`	`* ..`
`116`	`117`	`* .. Executable Statements ..`
`117`	`118`	`*`
`118`	`119`	`* Quick return if possible`
`119`	`120`	`*`
`120`	`121`	`IF( N.LE.0 )`
`121`	`122`	`$ RETURN`
	`123`	`+*`
	`124`	`+ IF( SA.GT.HUGE(SA) .OR. SA.LT.-HUGE(SA) ) THEN`
	`125`	`+ CALL ZDSCAL( N, SA, SX, INCX )`
	`126`	`+ RETURN`
	`127`	`+ END IF`
`122`	`128`	`*`
`123`	`129`	`* Get machine parameters`
`124`	`130`	`*`