On Mon, Sep 21, 2015 at 8:17 PM, Marc Glisse <marc.gli...@inria.fr> wrote: > On Mon, 21 Sep 2015, Daniel Gutson wrote: > >> This is derived from https://gcc.gnu.org/ml/gcc-help/2015-03/msg00091.html >> >> Currently, gcc provides an optimization that transforms a call to >> malloc and a call to memset into a call to calloc. >> This is fine except when it takes place within the calloc() function >> implementation itself, causing a recursive call. >> Two alternatives have been proposed: -fno-malloc-builtin and disable >> optimizations in calloc(). >> I think the former is suboptimal since it affects all the code just >> because of the implementation of one function (calloc()), >> whereas the latter is suboptimal too since it disables the >> optimizations in the whole function (calloc too). >> I think of two alternatives: either make -fno-calloc-builtin to >> disable the optimization, or make the optimization aware of the >> function context where it is operating and prevent it to do the >> transformation if the function is calloc(). >> >> Please help me to find the best alternative so we can implent it. > > > You may want to read this PR for more context > > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56888#c27
Yeah, I think the proper way is to add a helper to symtab to query whether the current function is BUILT_IN_XXX and use that to fend of most of the "obvious" cases. Richard. > -- > Marc Glisse
