debug option

• add -g -O0 when compiling original code:
  • -g produce debug info
  • -O0 optimization option

debug dynamic lib

• make sure program can be ran ( all env are correctly set)
• gdb
• breakpoint //function can be in the lib, e.g. class::func . gdb will ask you "Make breakpoint pending on future shared library load? (y or [n]) " answer y.
• run // it will stop at the breakpoint.,

-- ChengguangZhu - 07 May 2014