This (2013) article[1], when talking about "High Entropy Bottom-up Randomization" says that:
"For compatibility reasons, this feature is disabled by default and must be enabled on a per-application basis. This is because some 64-bit applications have latent pointer truncation issues that can surface when dealing with pointers above 4 GB (significant bits set beyond bit 31)."
Although OP had an issue with an offset rather than an absolute position, I imagine it would also handle that case.
"For compatibility reasons, this feature is disabled by default and must be enabled on a per-application basis. This is because some 64-bit applications have latent pointer truncation issues that can surface when dealing with pointers above 4 GB (significant bits set beyond bit 31)."
Although OP had an issue with an offset rather than an absolute position, I imagine it would also handle that case.
[1] https://msrc-blog.microsoft.com/2013/12/11/software-defense-...