Hello, I am trying to add a new gimple_opt pass to gcc 5.2. I wrote a simple test code to register a new pass that also has a flag. I added the pass in passes.def and also declared it in tree-pass.h. I recompiled gcc and it seems that my pass gets called (I printed some output in the execute() function) when compiling gcc itself, but not if I use gcc on an external file, for e.g: I expect that whenever I call: gcc -fsafestack file.c the pass would also be run on the code, but instead nothing happens. For reference, the code for the pass is here [1] and the pass registration and the flag are here[2]. Any help would be appreciated, Cristina [1] https://github.com/cristina2689/gcc/commit/350bfe6c408a96b1d3fad6191919759d83ad45b7 [2] https://github.com/cristina2689/gcc/commit/bae01349d17160261f52f9002dc469500e0bab27