Buidling antlr4 on AIX with GCC

I'm attempting to build the most recent clone of antlr4 on AIX 7.2 TL4 with GCC 8.3.0 targeting C++. When attempting to compile I run into ton of the following errors:

Does anyone have any ideas on how to fix this?

Start by reproducing the C++ build from a current ANTLR4 clone on AIX 7.2 TL4 with GCC 8.3.0 and capture the complete compiler output behind the linked image. Identify the affected build entry point and determine whether the build completes without the reported errors; document the required fix or confirm the platform limitation.

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