nm symbol output t vs T in a shared so library

Any idea about what I might be doing wrong?

The t function is indeed local to the library. This could happen due to a number or reasons. The most likely ones are:

1. You declared the function static, or
2. You compiled the library with -fvisibility=hidden and did not have __attribute__((visibility("default"))) on the function, or
3. You linked this library with a linker version script (i.e. with --version-script=libfoo.version flag) that hides all functions, except those which are explicitly exported, and you didn’t add your function to that list.

   See this example of using --version-script to limit symbol visibility.