succd and predd don't work properly on negative numbers

[academysoftwarefoundation]

succd and predd don't work properly on negative numbers

[peterhillman]

This would be a simple fix. Seems these functions aren't used by OpenEXR. Probably worth changing for the OpenEXR-2.0 release?

diff --git a/IlmBase/Imath/ImathFun.cpp b/IlmBase/Imath/ImathFun.cpp
index 9209ff8..65cf620 100644
--- a/IlmBase/Imath/ImathFun.cpp
+++ b/IlmBase/Imath/ImathFun.cpp
@@ -124,7 +124,7 @@ succd (double d)

         u.i = 0x0000000000000001LL;
     }
-    else if (u.i > 0)
+    else if (u.d > 0)
     {
         // Positive double, normalized or denormalized.
         // Incrementing the largest positive double
@@ -159,7 +159,7 @@ predd (double d)

         u.i = 0x8000000000000001LL;
     }
-    else if (u.i > 0)
+    else if (u.d > 0)
     {
         // Positive double, normalized or denormalized.

ImathTest output:

d 1
sd 1.00000000000000022
pd 0.999999999999999889
spd 1
psd 1

d -1
sd -0.999999999999999889
pd -1.00000000000000022
spd -1
psd -1

old output:
d -1
sd -1.00000000000000022
pd -0.999999999999999889
spd -1
psd -1

[peterhillman]

Applied in 090505e - will only affect OpenEXR-2.0 and later release