+||#
+\f
+;;; bug 120a: Turned out to be constraining code looking like (if foo
+;;; <X> <X>) where <X> was optimized by the compiler to be the exact
+;;; same block in both cases, but not turned into (PROGN FOO <X>).
+;;; Fixed by APD in sbcl-0.7.7.2, who provided this test:
+(declaim (inline dont-constrain-if-too-much))
+(defun dont-constrain-if-too-much (frame up-frame)
+ (declare (optimize (speed 3) (safety 1) (debug 1)))
+ (if (or (not frame) t)
+ frame
+ "bar"))
+(defun dont-constrain-if-too-much-aux (x y)
+ (declare (optimize (speed 3) (safety 1) (debug 1)))
+ (if x t (if y t (dont-constrain-if-too-much x y))))
+
+(assert (null (dont-constrain-if-too-much-aux nil nil)))