In Xcode, type Command-Shift-B to analyze every source file or Command-Shift-Control-B to analyze the current source file.
For pseudo_dma_read report FIFO underrun and init data_word in that case.
Result of running IWYU (https://include-what-you-use.org/) and
applying most of the suggestions about unncessary includes and
forward declarations.
Was motivated by observing that <thread> was being included in
ppcopcodes.cpp even though it was unused (found while researching
the use of threads), but seems generally good to help with build
times and correctness.
