Add 'gen_deps' variable
This will allow targets to ensure that other targets in non-default
toolchains will get generated even when they're not transitively
included in the build graph.
Change-Id: I5369f2440c02d3b3b8ef9bee598a37c95b8bfbeb
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/12280
Reviewed-by: Brett Wilson <brettw@chromium.org>
Commit-Queue: Brett Wilson <brettw@chromium.org>
diff --git a/misc/vim/syntax/gn.vim b/misc/vim/syntax/gn.vim
index 79faa70..851cec6 100644
--- a/misc/vim/syntax/gn.vim
+++ b/misc/vim/syntax/gn.vim
@@ -51,7 +51,7 @@
syn keyword gnVariable lib_dirs libs output_extension output_name outputs
syn keyword gnVariable public public_configs public_deps scripte sources
syn keyword gnVariable testonly visibility contents output_conversion rebase
-syn keyword gnVariable walk_keys
+syn keyword gnVariable walk_keys gen_deps
hi def link gnVariable Keyword
" Strings
diff --git a/src/gn/builder.cc b/src/gn/builder.cc
index d31eaa4..d1ba662 100644
--- a/src/gn/builder.cc
+++ b/src/gn/builder.cc
@@ -238,6 +238,7 @@
!AddDeps(record, target->configs().vector(), err) ||
!AddDeps(record, target->all_dependent_configs(), err) ||
!AddDeps(record, target->public_configs(), err) ||
+ !AddGenDeps(record, target->gen_deps(), err) ||
!AddActionValuesDep(record, target->action_values(), err) ||
!AddToolchainDep(record, target, err))
return false;
@@ -404,6 +405,19 @@
return true;
}
+bool Builder::AddGenDeps(BuilderRecord* record,
+ const LabelTargetVector& targets,
+ Err* err) {
+ for (const auto& target : targets) {
+ BuilderRecord* dep_record = GetOrCreateRecordOfType(
+ target.label, target.origin, BuilderRecord::ITEM_TARGET, err);
+ if (!dep_record)
+ return false;
+ record->AddGenDep(dep_record);
+ }
+ return true;
+}
+
bool Builder::AddActionValuesDep(BuilderRecord* record,
const ActionValues& action_values,
Err* err) {
@@ -435,6 +449,9 @@
void Builder::RecursiveSetShouldGenerate(BuilderRecord* record, bool force) {
if (!record->should_generate()) {
+ // This function can encounter cycles because gen_deps aren't a DAG. Setting
+ // the should_generate flag before iterating avoids infinite recursion in
+ // that case.
record->set_should_generate(true);
// This may have caused the item to go into "resolved and generated" state.
diff --git a/src/gn/builder.h b/src/gn/builder.h
index 8f328fa..bd62c18 100644
--- a/src/gn/builder.h
+++ b/src/gn/builder.h
@@ -94,6 +94,9 @@
bool AddDeps(BuilderRecord* record,
const LabelTargetVector& targets,
Err* err);
+ bool AddGenDeps(BuilderRecord* record,
+ const LabelTargetVector& targets,
+ Err* err);
bool AddActionValuesDep(BuilderRecord* record,
const ActionValues& action_values,
Err* err);
diff --git a/src/gn/builder_record.cc b/src/gn/builder_record.cc
index cbe8dae..6325cdc 100644
--- a/src/gn/builder_record.cc
+++ b/src/gn/builder_record.cc
@@ -58,6 +58,12 @@
return ITEM_UNKNOWN;
}
+void BuilderRecord::AddGenDep(BuilderRecord* record) {
+ // Records don't have to wait on resolution of their gen deps, since all they
+ // need to do is propagate should_generate to them.
+ all_deps_.insert(record);
+}
+
void BuilderRecord::AddDep(BuilderRecord* record) {
all_deps_.insert(record);
if (!record->resolved()) {
diff --git a/src/gn/builder_record.h b/src/gn/builder_record.h
index 989c239..439893b 100644
--- a/src/gn/builder_record.h
+++ b/src/gn/builder_record.h
@@ -74,7 +74,8 @@
bool can_resolve() const { return item_ && unresolved_deps_.empty(); }
- // All records this one is depending on.
+ // All records this one is depending on. Note that this includes gen_deps for
+ // targets, which can have cycles.
BuilderRecordSet& all_deps() { return all_deps_; }
const BuilderRecordSet& all_deps() const { return all_deps_; }
@@ -89,6 +90,7 @@
return waiting_on_resolution_;
}
+ void AddGenDep(BuilderRecord* record);
void AddDep(BuilderRecord* record);
private:
diff --git a/src/gn/builder_unittest.cc b/src/gn/builder_unittest.cc
index b0f48f0..81b9f89 100644
--- a/src/gn/builder_unittest.cc
+++ b/src/gn/builder_unittest.cc
@@ -2,10 +2,13 @@
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
+#include <algorithm>
+
#include "gn/builder.h"
#include "gn/config.h"
#include "gn/loader.h"
#include "gn/target.h"
+#include "gn/test_with_scheduler.h"
#include "gn/test_with_scope.h"
#include "gn/toolchain.h"
#include "util/test/test.h"
@@ -55,6 +58,9 @@
files_.clear();
return match;
}
+ bool HasLoadedOnce(const SourceFile& f) {
+ return count(files_.begin(), files_.end(), f) == 1;
+ }
private:
~MockLoader() override = default;
@@ -62,7 +68,7 @@
std::vector<SourceFile> files_;
};
-class BuilderTest : public testing::Test {
+class BuilderTest : public TestWithScheduler {
public:
BuilderTest()
: loader_(new MockLoader),
@@ -223,6 +229,92 @@
EXPECT_TRUE(b_record->should_generate());
}
+// Test that "gen_deps" forces targets to be generated.
+TEST_F(BuilderTest, GenDeps) {
+ DefineToolchain();
+
+ // Define another toolchain
+ Settings settings2(&build_settings_, "alternate/");
+ Label alt_tc(SourceDir("//tc/"), "alternate");
+ settings2.set_toolchain_label(alt_tc);
+ Toolchain* tc2 = new Toolchain(&settings2, alt_tc);
+ TestWithScope::SetupToolchain(tc2);
+ builder_.ItemDefined(std::unique_ptr<Item>(tc2));
+
+ // Construct the dependency chain A -> B -gen-> C -gen-> D where A is the only
+ // target in the default toolchain. This should cause all 4 targets to be
+ // generated.
+ Label a_label(SourceDir("//a/"), "a", settings_.toolchain_label().dir(),
+ settings_.toolchain_label().name());
+ Label b_label(SourceDir("//b/"), "b", alt_tc.dir(), alt_tc.name());
+ Label c_label(SourceDir("//c/"), "c", alt_tc.dir(), alt_tc.name());
+ Label d_label(SourceDir("//d/"), "d", alt_tc.dir(), alt_tc.name());
+
+ Target* c = new Target(&settings2, c_label);
+ c->set_output_type(Target::EXECUTABLE);
+ c->gen_deps().push_back(LabelTargetPair(d_label));
+ builder_.ItemDefined(std::unique_ptr<Item>(c));
+
+ Target* b = new Target(&settings2, b_label);
+ b->set_output_type(Target::EXECUTABLE);
+ b->gen_deps().push_back(LabelTargetPair(c_label));
+ builder_.ItemDefined(std::unique_ptr<Item>(b));
+
+ Target* a = new Target(&settings_, a_label);
+ a->set_output_type(Target::EXECUTABLE);
+ a->private_deps().push_back(LabelTargetPair(b_label));
+ builder_.ItemDefined(std::unique_ptr<Item>(a));
+
+ // At this point, "should generate" should have propogated to C which should
+ // request for D to be loaded
+ EXPECT_TRUE(loader_->HasLoadedOnce(SourceFile("//d/BUILD.gn")));
+
+ Target* d = new Target(&settings2, d_label);
+ d->set_output_type(Target::EXECUTABLE);
+ builder_.ItemDefined(std::unique_ptr<Item>(d));
+
+ BuilderRecord* a_record = builder_.GetRecord(a_label);
+ BuilderRecord* b_record = builder_.GetRecord(b_label);
+ BuilderRecord* c_record = builder_.GetRecord(c_label);
+ BuilderRecord* d_record = builder_.GetRecord(d_label);
+ EXPECT_TRUE(a_record->should_generate());
+ EXPECT_TRUE(b_record->should_generate());
+ EXPECT_TRUE(c_record->should_generate());
+ EXPECT_TRUE(d_record->should_generate());
+}
+
+// Test that circular dependencies between gen_deps and deps are allowed
+TEST_F(BuilderTest, GenDepsCircle) {
+ DefineToolchain();
+ Settings settings2(&build_settings_, "alternate/");
+ Label alt_tc(SourceDir("//tc/"), "alternate");
+ settings2.set_toolchain_label(alt_tc);
+ Toolchain* tc2 = new Toolchain(&settings2, alt_tc);
+ TestWithScope::SetupToolchain(tc2);
+ builder_.ItemDefined(std::unique_ptr<Item>(tc2));
+
+ // A is in the default toolchain and lists B as a gen_dep
+ // B is in an alternate toolchain and lists A as a normal dep
+ Label a_label(SourceDir("//a/"), "a", settings_.toolchain_label().dir(),
+ settings_.toolchain_label().name());
+ Label b_label(SourceDir("//b/"), "b", alt_tc.dir(), alt_tc.name());
+
+ Target* a = new Target(&settings_, a_label);
+ a->gen_deps().push_back(LabelTargetPair(b_label));
+ a->set_output_type(Target::EXECUTABLE);
+ builder_.ItemDefined(std::unique_ptr<Item>(a));
+
+ Target* b = new Target(&settings2, b_label);
+ b->private_deps().push_back(LabelTargetPair(a_label));
+ b->set_output_type(Target::EXECUTABLE);
+ builder_.ItemDefined(std::unique_ptr<Item>(b));
+
+ Err err;
+ EXPECT_TRUE(builder_.CheckForBadItems(&err));
+ BuilderRecord* b_record = builder_.GetRecord(b_label);
+ EXPECT_TRUE(b_record->should_generate());
+}
+
// Tests that configs applied to a config get loaded (bug 536844).
TEST_F(BuilderTest, ConfigLoad) {
SourceDir toolchain_dir = settings_.toolchain_label().dir();
diff --git a/src/gn/command_desc.cc b/src/gn/command_desc.cc
index 82a3822..fcb3434 100644
--- a/src/gn/command_desc.cc
+++ b/src/gn/command_desc.cc
@@ -296,6 +296,7 @@
{variables::kPrecompiledHeader, DefaultHandler},
{variables::kPrecompiledSource, DefaultHandler},
{variables::kDeps, DepsHandler},
+ {variables::kGenDeps, DefaultHandler},
{variables::kLibs, DefaultHandler},
{variables::kLibDirs, DefaultHandler},
{variables::kDataKeys, DefaultHandler},
diff --git a/src/gn/desc_builder.cc b/src/gn/desc_builder.cc
index 3b6ab23..5a8fc4c 100644
--- a/src/gn/desc_builder.cc
+++ b/src/gn/desc_builder.cc
@@ -52,6 +52,7 @@
// "precompiled_header" : "name of precompiled header file",
// "precompiled_source" : "path to precompiled source",
// "deps : [ list of target dependencies ],
+// "gen_deps : [ list of generate dependencies ],
// "libs" : [ list of libraries ],
// "lib_dirs" : [ list of library directories ]
// "metadata" : [ dictionary of target metadata values ]
@@ -569,6 +570,9 @@
if (what(variables::kDeps))
res->SetWithoutPathExpansion(variables::kDeps, RenderDeps());
+ if (what(variables::kGenDeps) && !target_->gen_deps().empty())
+ res->SetWithoutPathExpansion(variables::kGenDeps, RenderGenDeps());
+
// Runtime deps are special, print only when explicitly asked for and not in
// overview mode.
if (what_.find("runtime_deps") != what_.end())
@@ -711,6 +715,18 @@
return std::move(res);
}
+ ValuePtr RenderGenDeps() {
+ auto res = std::make_unique<base::ListValue>();
+ Label default_tc = target_->settings()->default_toolchain_label();
+ std::vector<std::string> gen_deps;
+ for (const auto& pair : target_->gen_deps())
+ gen_deps.push_back(pair.label.GetUserVisibleName(default_tc));
+ std::sort(gen_deps.begin(), gen_deps.end());
+ for (const auto& dep : gen_deps)
+ res->AppendString(dep);
+ return std::move(res);
+ }
+
ValuePtr RenderRuntimeDeps() {
auto res = std::make_unique<base::ListValue>();
diff --git a/src/gn/target.cc b/src/gn/target.cc
index 1dcd88d..da6b7e4 100644
--- a/src/gn/target.cc
+++ b/src/gn/target.cc
@@ -260,6 +260,13 @@
required (directly or transitively) to build a target in the default
toolchain.
+ Some targets might be associated but without a formal build dependency (for
+ example, related tools or optional variants). A target that is marked as
+ "generated" can propagate its generated state to an associated target using
+ "gen_deps". This will make the referenced dependency have Ninja rules
+ generated in the same cases the source target has but without a build-time
+ dependency and even in non-default toolchains.
+
See also "gn help ninja_rules".
Dependencies
diff --git a/src/gn/target.h b/src/gn/target.h
index 590d78e..59fe806 100644
--- a/src/gn/target.h
+++ b/src/gn/target.h
@@ -262,6 +262,11 @@
const LabelTargetVector& data_deps() const { return data_deps_; }
LabelTargetVector& data_deps() { return data_deps_; }
+ // gen_deps only propagate the "should_generate" flag. These dependencies can
+ // have cycles so care should be taken if iterating over them recursively.
+ const LabelTargetVector& gen_deps() const { return gen_deps_; }
+ LabelTargetVector& gen_deps() { return gen_deps_; }
+
// List of configs that this class inherits settings from. Once a target is
// resolved, this will also list all-dependent and public configs.
const UniqueVector<LabelConfigPair>& configs() const { return configs_; }
@@ -477,6 +482,7 @@
LabelTargetVector private_deps_;
LabelTargetVector public_deps_;
LabelTargetVector data_deps_;
+ LabelTargetVector gen_deps_;
// See getters for more info.
UniqueVector<LabelConfigPair> configs_;
diff --git a/src/gn/target_generator.cc b/src/gn/target_generator.cc
index 0ae9daf..4138889 100644
--- a/src/gn/target_generator.cc
+++ b/src/gn/target_generator.cc
@@ -260,6 +260,8 @@
return false;
if (!FillGenericDeps(variables::kDataDeps, &target_->data_deps()))
return false;
+ if (!FillGenericDeps(variables::kGenDeps, &target_->gen_deps()))
+ return false;
// "data_deps" was previously named "datadeps". For backwards-compat, read
// the old one if no "data_deps" were specified.
diff --git a/src/gn/variables.cc b/src/gn/variables.cc
index 285f3b9..433d280 100644
--- a/src/gn/variables.cc
+++ b/src/gn/variables.cc
@@ -12,10 +12,9 @@
// Built-in variables ----------------------------------------------------------
const char kGnVersion[] = "gn_version";
-const char kGnVersion_HelpShort[] =
- "gn_version: [number] The version of gn.";
+const char kGnVersion_HelpShort[] = "gn_version: [number] The version of gn.";
const char kGnVersion_Help[] =
- R"(gn_version: [number] The version of gn.
+ R"(gn_version: [number] The version of gn.
Corresponds to the number printed by `gn --version`.
@@ -411,7 +410,7 @@
" those configs appear in the list.\n" \
" 5. all_dependent_configs pulled from dependencies, in the order of\n" \
" the \"deps\" list. This is done recursively. If a config appears\n" \
- " more than once, only the first occurrence will be used.\n" \
+ " more than once, only the first occurrence will be used.\n" \
" 6. public_configs pulled from dependencies, in the order of the\n" \
" \"deps\" list. If a dependency is public, they will be applied\n" \
" recursively.\n"
@@ -509,6 +508,23 @@
}
)";
+const char kGenDeps[] = "gen_deps";
+const char kGenDeps_HelpShort[] =
+ "gen_deps: [label list] "
+ "Declares targets that should generate when this one does.";
+const char kGenDeps_Help[] =
+ R"(gen_deps: Declares targets that should generate when this one does.
+
+ A list of target labels.
+
+ Not all GN targets that get evaluated are actually turned into ninja targets
+ (see "gn help execution"). If this target is generated, then any targets in
+ the "gen_deps" list will also be generated, regardless of the usual critera.
+
+ Since "gen_deps" are not build time dependencies, there can be cycles between
+ "deps" and "gen_deps" or within "gen_deps" itself.
+)";
+
const char kArflags[] = "arflags";
const char kArflags_HelpShort[] =
"arflags: [string list] Arguments passed to static_library archiver.";
@@ -2265,6 +2281,7 @@
if (info_map.empty()) {
INSERT_VARIABLE(AllDependentConfigs)
INSERT_VARIABLE(AllowCircularIncludesFrom)
+ INSERT_VARIABLE(GenDeps)
INSERT_VARIABLE(Arflags)
INSERT_VARIABLE(Args)
INSERT_VARIABLE(Asmflags)
diff --git a/src/gn/variables.h b/src/gn/variables.h
index f5794d1..169a5af 100644
--- a/src/gn/variables.h
+++ b/src/gn/variables.h
@@ -354,6 +354,10 @@
extern const char kXcodeExtraAttributes_HelpShort[];
extern const char kXcodeExtraAttributes_Help[];
+extern const char kGenDeps[];
+extern const char kGenDeps_HelpShort[];
+extern const char kGenDeps_Help[];
+
// -----------------------------------------------------------------------------
struct VariableInfo {
