32-bit App with dynamic library crash on 64-bit device

Question

I am facing the following scenario:

• 32 bit device + app armv7 + dynamic library armv7 arm64 = work
• 64 bit device + app armv7 + dynamic library armv7 arm64 = doesn't work

doesn't work - app crashes on load with the following error:

dyld error message library not loaded reason no suitable image found

Any explanations?

Answer 1

Explanation : 32 bit binaries loaded on 64 bit devices fail to do so since the 32 bit pagesize has been changed from 4096 bytes to 16384 bytes in iOS 9.

Conclusion : 32-bit apps with dynamic libraries cannot run on 64-bit devices.

Solutions (one of the two is enough):

• Add a new entry to Other linker flags in the dynamic library project:

  -Wl,-segalign,4000

• Update app itself to support arm64 architecture