I've updated https://bugzilla.samba.org/show_bug.cgi?id=8424.
Perhaps a rename is needed as the title implies it is ubuntu specific and intermittant? On 18 October 2013 11:05, Ian Norton <inor...@gmail.com> wrote: > Ok. I should have tried it before hand. ccache *doesnt't* notice the > addition of the new header and still gives me a .o file from the first > invocation. > > bug? > > On 18 October 2013 10:54, Ian Norton <inor...@gmail.com> wrote: >> Hello All, >> >> I have a question about direct mode, it follows on from an old thread >> I've seen in the archives: >> >> http://www.mail-archive.com/ccache@lists.samba.org/msg00150.html >> >> I'll quote inline and follow on. >> >> Joel Rosdahl wrote: >>> tridge wrote: >>> > Also, does the hashtable used for included_files preserve the >>> > ordering? (the order of includes is also vital). Or do you rely on the >>> > hash of the file that does the #include changing for that? >> >>> The hashtable is unordered, and yes, I rely on the hash of the input >>> file to keep track of the ordering, and also of course on the include >>> file hashes. For a given manifest, the source file (and therefore the >>> order of the first level of include files) is known since the manifest >>> is looked up given the hash of the input file (and some more >>> information), and all other levels of include files are taken >>> care of using the same kind of reasoning. In other words, if the >>> include file order changes in some file, then the hash of that file >>> changes too, which leads to a cache miss. Which include files the >>> preprocessor reads is of course also a function of compiler options >>> like -I, but that is handled by also hashing those options when >>> computing the hash in direct mode. Do you see any potential problem >>> here? >> >> I realise I'm probably missing something, but how does direct mode >> handle the case where >> the command line args have not changed, and nor have the source file >> or previously used headers *but* a header file has been added to a >> folder on one of the -I paths? eg: >> >> hello.c: >> #include "test.h" >> >> inc1/test.h: >> void hello(void); >> >> gcc -I inc2 -I inc1 -c hello.c >> >> later, someone makes a new file: >> >> inc2/test.h: >> int hello(void); >> >> The same command line and original inputs would result in a different file. >> >> How does direct mode cover this case ( all our common input data has >> not changed ) >> >> Many Thanks, ccache is fantastic btw! >> >> Ian _______________________________________________ ccache mailing list ccache@lists.samba.org https://lists.samba.org/mailman/listinfo/ccache
