diff options
Diffstat (limited to 'build/cxx/compile.cxx')
| -rw-r--r-- | build/cxx/compile.cxx | 794 |
1 files changed, 0 insertions, 794 deletions
diff --git a/build/cxx/compile.cxx b/build/cxx/compile.cxx deleted file mode 100644 index 2481b62..0000000 --- a/build/cxx/compile.cxx +++ /dev/null @@ -1,794 +0,0 @@ -// file : build/cxx/compile.cxx -*- C++ -*- -// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd -// license : MIT; see accompanying LICENSE file - -#include <build/cxx/compile> - -#include <map> -#include <string> -#include <cstddef> // size_t -#include <cstdlib> // exit() -#include <utility> // move() - -#include <butl/process> -#include <butl/utility> // reverse_iterate -#include <butl/fdstream> -#include <butl/path-map> - -#include <build/types> -#include <build/scope> -#include <build/variable> -#include <build/algorithm> -#include <build/diagnostics> -#include <build/context> - -#include <build/bin/target> -#include <build/cxx/target> - -#include <build/cxx/utility> -#include <build/cxx/link> - -using namespace std; -using namespace butl; - -namespace build -{ - namespace cxx - { - using namespace bin; - - match_result compile:: - match (action a, target& t, const string&) const - { - tracer trace ("cxx::compile::match"); - - // @@ TODO: - // - // - check prerequisites: single source file - // - if path already assigned, verify extension? - // - - // See if we have a C++ source file. Iterate in reverse so that - // a source file specified for an obj*{} member overrides the one - // specified for the group. Also "see through" groups. - // - for (prerequisite_member p: reverse_group_prerequisite_members (a, t)) - { - if (p.is_a<cxx> ()) - return p; - } - - level4 ([&]{trace << "no c++ source file for target " << t;}); - return nullptr; - } - - static void - inject_prerequisites (action, target&, cxx&, scope&); - - recipe compile:: - apply (action a, target& xt, const match_result& mr) const - { - path_target& t (static_cast<path_target&> (xt)); - - // Derive file name from target name. - // - if (t.path ().empty ()) - t.derive_path ("o", nullptr, (t.is_a<objso> () ? "-so" : nullptr)); - - // Inject dependency on the output directory. - // - inject_parent_fsdir (a, t); - - // Search and match all the existing prerequisites. The injection - // code (below) takes care of the ones it is adding. - // - // When cleaning, ignore prerequisites that are not in the same - // or a subdirectory of our strong amalgamation. - // - const dir_path* amlg ( - a.operation () != clean_id - ? nullptr - : &t.strong_scope ().out_path ()); - - link::search_paths_cache lib_paths; // Extract lazily. - - for (prerequisite_member p: group_prerequisite_members (a, t)) - { - // A dependency on a library is there so that we can get its - // cxx.export.poptions. In particular, making sure it is - // executed before us will only restrict parallelism. But we - // do need to pre-match it in order to get its - // prerequisite_targets populated. This is the "library - // meta-information protocol". See also append_lib_options() - // above. - // - if (p.is_a<lib> () || p.is_a<liba> () || p.is_a<libso> ()) - { - if (a.operation () == update_id) - { - // Handle imported libraries. We know that for such libraries - // we don't need to do match() in order to get options (if - // any, they would be set by search_library()). - // - if (p.proj () == nullptr || - link::search_library (lib_paths, p.prerequisite) == nullptr) - { - match_only (a, p.search ()); - } - } - - continue; - } - - target& pt (p.search ()); - - if (a.operation () == clean_id && !pt.dir.sub (*amlg)) - continue; - - build::match (a, pt); - t.prerequisite_targets.push_back (&pt); - } - - // Inject additional prerequisites. We only do it when - // performing update since chances are we will have to - // update some of our prerequisites in the process (auto- - // generated source code). - // - if (a == perform_update_id) - { - // The cached prerequisite target should be the same as what - // is in t.prerequisite_targets since we used standard - // search() and match() above. - // - // @@ Ugly. - // - cxx& st ( - dynamic_cast<cxx&> ( - mr.target != nullptr ? *mr.target : *mr.prerequisite->target)); - inject_prerequisites (a, t, st, mr.prerequisite->scope); - } - - switch (a) - { - case perform_update_id: return &perform_update; - case perform_clean_id: return &perform_clean; - default: return noop_recipe; // Configure update. - } - } - - // Reverse-lookup target type from extension. - // - static const target_type* - map_extension (scope& s, const string& n, const string& e) - { - // We will just have to try all of the possible ones, in the - // "most likely to match" order. - // - const variable& var (var_pool.find ("extension")); - - auto test = [&s, &n, &e, &var] (const target_type& tt) - -> const target_type* - { - if (auto l = s.lookup (tt, n, var)) - if (as<string> (*l) == e) - return &tt; - - return nullptr; - }; - - if (auto r = test (hxx::static_type)) return r; - if (auto r = test (h::static_type)) return r; - if (auto r = test (ixx::static_type)) return r; - if (auto r = test (txx::static_type)) return r; - if (auto r = test (cxx::static_type)) return r; - if (auto r = test (c::static_type)) return r; - - return nullptr; - } - - // Mapping of include prefixes (e.g., foo in <foo/bar>) for auto- - // generated headers to directories where they will be generated. - // - // We are using a prefix map of directories (dir_path_map) instead - // of just a map in order also cover sub-paths (e.g., <foo/more/bar> - // if we continue with the example). Specifically, we need to make - // sure we don't treat foobar as a sub-directory of foo. - // - // @@ The keys should be canonicalized. - // - using prefix_map = dir_path_map<dir_path>; - - static void - append_prefixes (prefix_map& m, target& t, const char* var) - { - tracer trace ("cxx::append_prefixes"); - - // If this target does not belong to any project (e.g, an - // "imported as installed" library), then it can't possibly - // generate any headers for us. - // - scope* rs (t.base_scope ().root_scope ()); - if (rs == nullptr) - return; - - const dir_path& out_base (t.dir); - const dir_path& out_root (rs->out_path ()); - - if (auto l = t[var]) - { - const auto& v (as<strings> (*l)); - - for (auto i (v.begin ()), e (v.end ()); i != e; ++i) - { - // -I can either be in the "-Ifoo" or "-I foo" form. - // - dir_path d; - if (*i == "-I") - { - if (++i == e) - break; // Let the compiler complain. - - d = dir_path (*i); - } - else if (i->compare (0, 2, "-I") == 0) - d = dir_path (*i, 2, string::npos); - else - continue; - - level6 ([&]{trace << "-I '" << d << "'";}); - - // If we are relative or not inside our project root, then - // ignore. - // - if (d.relative () || !d.sub (out_root)) - continue; - - // If the target directory is a sub-directory of the include - // directory, then the prefix is the difference between the - // two. Otherwise, leave it empty. - // - // The idea here is to make this "canonical" setup work auto- - // magically: - // - // 1. We include all files with a prefix, e.g., <foo/bar>. - // 2. The library target is in the foo/ sub-directory, e.g., - // /tmp/foo/. - // 3. The poptions variable contains -I/tmp. - // - dir_path p (out_base.sub (d) ? out_base.leaf (d) : dir_path ()); - - auto j (m.find (p)); - - if (j != m.end ()) - { - if (j->second != d) - { - // We used to reject duplicates but it seems this can - // be reasonably expected to work according to the order - // of the -I options. - // - if (verb >= 4) - trace << "overriding dependency prefix '" << p << "'\n" - << " old mapping to " << j->second << "\n" - << " new mapping to " << d; - - j->second = d; - } - } - else - { - level6 ([&]{trace << "'" << p << "' = '" << d << "'";}); - m.emplace (move (p), move (d)); - } - } - } - } - - // Append library prefixes based on the cxx.export.poptions variables - // recursively, prerequisite libraries first. - // - static void - append_lib_prefixes (prefix_map& m, target& l) - { - for (target* t: l.prerequisite_targets) - { - if (t == nullptr) - continue; - - if (t->is_a<lib> () || t->is_a<liba> () || t->is_a<libso> ()) - append_lib_prefixes (m, *t); - } - - append_prefixes (m, l, "cxx.export.poptions"); - } - - static prefix_map - build_prefix_map (target& t) - { - prefix_map m; - - // First process the include directories from prerequisite - // libraries. Note that here we don't need to see group - // members (see apply()). - // - for (prerequisite& p: group_prerequisites (t)) - { - target& pt (*p.target); // Already searched and matched. - - if (pt.is_a<lib> () || pt.is_a<liba> () || pt.is_a<libso> ()) - append_lib_prefixes (m, pt); - } - - // Then process our own. - // - append_prefixes (m, t, "cxx.poptions"); - - return m; - } - - // Return the next make prerequisite starting from the specified - // position and update position to point to the start of the - // following prerequisite or l.size() if there are none left. - // - static string - next (const string& l, size_t& p) - { - size_t n (l.size ()); - - // Skip leading spaces. - // - for (; p != n && l[p] == ' '; p++) ; - - // Lines containing multiple prerequisites are 80 characters max. - // - string r; - r.reserve (n); - - // Scan the next prerequisite while watching out for escape sequences. - // - for (; p != n && l[p] != ' '; p++) - { - char c (l[p]); - - if (c == '\\') - c = l[++p]; - - r += c; - } - - // Skip trailing spaces. - // - for (; p != n && l[p] == ' '; p++) ; - - // Skip final '\'. - // - if (p == n - 1 && l[p] == '\\') - p++; - - return r; - } - - static void - inject_prerequisites (action a, target& t, cxx& s, scope& ds) - { - tracer trace ("cxx::compile::inject_prerequisites"); - - scope& rs (t.root_scope ()); - const string& cxx (as<string> (*rs["config.cxx"])); - - cstrings args {cxx.c_str ()}; - - // Add cxx.export.poptions from prerequisite libraries. Note - // that here we don't need to see group members (see apply()). - // - for (prerequisite& p: group_prerequisites (t)) - { - target& pt (*p.target); // Already searched and matched. - - if (pt.is_a<lib> () || pt.is_a<liba> () || pt.is_a<libso> ()) - append_lib_options (args, pt, "cxx.export.poptions"); - } - - append_options (args, t, "cxx.poptions"); - - // @@ Some C++ options (e.g., -std, -m) affect the preprocessor. - // Or maybe they are not C++ options? Common options? - // - append_options (args, t, "cxx.coptions"); - - string std; // Storage. - append_std (args, t, std); - - if (t.is_a<objso> ()) - args.push_back ("-fPIC"); - - args.push_back ("-M"); // Note: -MM -MG skips missing <>-included. - args.push_back ("-MG"); // Treat missing headers as generated. - args.push_back ("-MQ"); // Quoted target name. - args.push_back ("*"); // Old versions can't handle empty target name. - - // We are using absolute source file path in order to get absolute - // paths in the result. Any relative paths in the result are non- - // existent, potentially auto-generated headers. - // - // @@ We will also have to use absolute -I paths to guarantee - // that. Or just detect relative paths and error out? - // - args.push_back (s.path ().string ().c_str ()); - args.push_back (nullptr); - - level6 ([&]{trace << "target: " << t;}); - - // Build the prefix map lazily only if we have non-existent files. - // Also reuse it over restarts since it doesn't change. - // - prefix_map pm; - - // If any prerequisites that we have extracted changed, then we - // have to redo the whole thing. The reason for this is auto- - // generated headers: the updated header may now include a yet- - // non-existent header. Unless we discover this and generate it - // (which, BTW, will trigger another restart since that header, - // in turn, can also include auto-generated headers), we will - // end up with an error during compilation proper. - // - // One complication with this restart logic is that we will see - // a "prefix" of prerequisites that we have already processed - // (i.e., they are already in our prerequisite_targets list) and - // we don't want to keep redoing this over and over again. One - // thing to note, however, is that the prefix that we have seen - // on the previous run must appear exactly the same in the - // subsequent run. The reason for this is that none of the files - // that it can possibly be based on have changed and thus it - // should be exactly the same. To put it another way, the - // presence or absence of a file in the dependency output can - // only depend on the previous files (assuming the compiler - // outputs them as it encounters them and it is hard to think - // of a reason why would someone do otherwise). And we have - // already made sure that all those files are up to date. And - // here is the way we are going to exploit this: we are going - // to keep track of how many prerequisites we have processed so - // far and on restart skip right to the next one. - // - // Also, before we do all that, make sure the source file itself - // if up to date. - // - execute_direct (a, s); - - size_t skip_count (0); - for (bool restart (true); restart; ) - { - restart = false; - - if (verb >= 3) - print_process (args); - - try - { - process pr (args.data (), 0, -1); // Open pipe to stdout. - ifdstream is (pr.in_ofd); - - size_t skip (skip_count); - for (bool first (true), second (true); !(restart || is.eof ()); ) - { - string l; - getline (is, l); - - if (is.fail () && !is.eof ()) - fail << "error reading C++ compiler -M output"; - - size_t pos (0); - - if (first) - { - // Empty output should mean the wait() call below will return - // false. - // - if (l.empty ()) - break; - - assert (l[0] == '*' && l[1] == ':' && l[2] == ' '); - - first = false; - - // While normally we would have the source file on the - // first line, if too long, it will be moved to the next - // line and all we will have on this line is "*: \". - // - if (l.size () == 4 && l[3] == '\\') - continue; - else - pos = 3; // Skip "*: ". - - // Fall through to the 'second' block. - } - - if (second) - { - second = false; - next (l, pos); // Skip the source file. - } - - // If things go wrong (and they often do in this area), give - // the user a bit extra context. - // - auto g ( - make_exception_guard ( - [&s]() - { - info << "while extracting dependencies from " << s; - })); - - while (pos != l.size ()) - { - string fs (next (l, pos)); - - // Skip until where we left off. - // - if (skip != 0) - { - skip--; - continue; - } - - path f (move (fs)); - f.normalize (); - - if (!f.absolute ()) - { - // This is probably as often an error as an auto-generated - // file, so trace at level 4. - // - level4 ([&]{trace << "non-existent header '" << f << "'";}); - - // If we already did it and build_prefix_map() returned empty, - // then we would have failed below. - // - if (pm.empty ()) - pm = build_prefix_map (t); - - // First try the whole file. Then just the directory. - // - // @@ Has to be a separate map since the prefix can be - // the same as the file name. - // - // auto i (pm.find (f)); - - // Find the most qualified prefix of which we are a - // sub-path. - // - auto i (pm.end ()); - - if (!pm.empty ()) - { - const dir_path& d (f.directory ()); - i = pm.upper_bound (d); - - // Get the greatest less than, if any. We might - // still not be a sub. Note also that we still - // have to check the last element is upper_bound() - // returned end(). - // - if (i == pm.begin () || !d.sub ((--i)->first)) - i = pm.end (); - } - - if (i == pm.end ()) - fail << "unable to map presumably auto-generated header '" - << f << "' to a project"; - - f = i->second / f; - } - - level6 ([&]{trace << "injecting " << f;}); - - // Split the name into its directory part, the name part, and - // extension. Here we can assume the name part is a valid - // filesystem name. - // - // Note that if the file has no extension, we record an empty - // extension rather than NULL (which would signify that the - // default extension should be added). - // - dir_path d (f.directory ()); - string n (f.leaf ().base ().string ()); - const char* es (f.extension ()); - const string* e (&extension_pool.find (es != nullptr ? es : "")); - - // Determine the target type. - // - const target_type* tt (nullptr); - - // See if this directory is part of any project out_root - // hierarchy. Note that this will miss all the headers - // that come from src_root (so they will be treated as - // generic C headers below). Generally, we don't have - // the ability to determine that some file belongs to - // src_root of some project. But that's not a problem - // for our purposes: it is only important for us to - // accurately determine target types for headers that - // could be auto-generated. - // - scope& b (scopes.find (d)); - if (b.root_scope () != nullptr) - tt = map_extension (b, n, *e); - - // If it is outside any project, or the project doesn't have - // such an extension, assume it is a plain old C header. - // - if (tt == nullptr) - tt = &h::static_type; - - // Find or insert target. - // - path_target& pt ( - static_cast<path_target&> (search (*tt, d, n, e, &ds))); - - // Assign path. - // - if (pt.path ().empty ()) - pt.path (move (f)); - - // Match to a rule. - // - build::match (a, pt); - - // Update it. - // - // There would normally be a lot of headers for every source - // file (think all the system headers) and this can get - // expensive. At the same time, most of these headers are - // existing files that we will never be updated (again, - // system headers, for example) and the rule that will match - // them is fallback file_rule. That rule has an optimization - // in that it returns noop_recipe (which causes the target - // state to be automatically set to unchanged) if the file - // is known to be up to date. - // - if (pt.state () != target_state::unchanged) - { - // We only want to restart if our call to execute() actually - // caused an update. In particular, the target could already - // have been in target_state::changed because of a dependency - // extraction run for some other source file. - // - target_state os (pt.state ()); - target_state ns (execute_direct (a, pt)); - - if (ns != os && ns != target_state::unchanged) - { - level6 ([&]{trace << "updated " << pt << ", restarting";}); - restart = true; - } - } - - // Add to our prerequisite target list. - // - t.prerequisite_targets.push_back (&pt); - skip_count++; - } - } - - // We may not have read all the output (e.g., due to a restart), - // so close the file descriptor before waiting to avoid blocking - // the other end. - // - is.close (); - - // We assume the child process issued some diagnostics. - // - if (!pr.wait ()) - { - // In case of a restarts, we closed our end of the pipe early - // which might have caused the other end to fail. So far we - // experienced this on Fedora 23 with GCC 5.3.1 and there were - // no diagnostics issued, just the non-zero exit status. If we - // do get diagnostics, then we will have to read and discard the - // output until eof. - // - if (!restart) - throw failed (); - } - } - catch (const process_error& e) - { - error << "unable to execute " << args[0] << ": " << e.what (); - - // In a multi-threaded program that fork()'ed but did not exec(), - // it is unwise to try to do any kind of cleanup (like unwinding - // the stack and running destructors). - // - if (e.child ()) - exit (1); - - throw failed (); - } - } - } - - target_state compile:: - perform_update (action a, target& xt) - { - path_target& t (static_cast<path_target&> (xt)); - cxx* s (execute_prerequisites<cxx> (a, t, t.mtime ())); - - if (s == nullptr) - return target_state::unchanged; - - // Translate paths to relative (to working directory) ones. This - // results in easier to read diagnostics. - // - path relo (relative (t.path ())); - path rels (relative (s->path ())); - - scope& rs (t.root_scope ()); - const string& cxx (as<string> (*rs["config.cxx"])); - - cstrings args {cxx.c_str ()}; - - // Add cxx.export.poptions from prerequisite libraries. Note that - // here we don't need to see group members (see apply()). - // - for (prerequisite& p: group_prerequisites (t)) - { - target& pt (*p.target); // Already searched and matched. - - if (pt.is_a<lib> () || pt.is_a<liba> () || pt.is_a<libso> ()) - append_lib_options (args, pt, "cxx.export.poptions"); - } - - append_options (args, t, "cxx.poptions"); - append_options (args, t, "cxx.coptions"); - - string std; // Storage. - append_std (args, t, std); - - if (t.is_a<objso> ()) - args.push_back ("-fPIC"); - - args.push_back ("-o"); - args.push_back (relo.string ().c_str ()); - - args.push_back ("-c"); - args.push_back (rels.string ().c_str ()); - - args.push_back (nullptr); - - if (verb >= 2) - print_process (args); - else if (verb) - text << "c++ " << *s; - - try - { - process pr (args.data ()); - - if (!pr.wait ()) - throw failed (); - - // Should we go to the filesystem and get the new mtime? We - // know the file has been modified, so instead just use the - // current clock time. It has the advantage of having the - // subseconds precision. - // - t.mtime (system_clock::now ()); - return target_state::changed; - } - catch (const process_error& e) - { - error << "unable to execute " << args[0] << ": " << e.what (); - - // In a multi-threaded program that fork()'ed but did not exec(), - // it is unwise to try to do any kind of cleanup (like unwinding - // the stack and running destructors). - // - if (e.child ()) - exit (1); - - throw failed (); - } - } - - compile compile::instance; - } -} |