Add incompatible flags for removing legacy cc_toolchain skylark apis
Progress on #4571.
RELNOTES: Added `--incompatible_disable_legacy_flags_cc_toolchain_api` to
deprecate legacy `cc_toolchain` Skylark API for legacy CROSSTOOL fields.
PiperOrigin-RevId: 214764514
diff --git a/site/docs/skylark/backward-compatibility.md b/site/docs/skylark/backward-compatibility.md
index 4561e25..6e0760d 100644
--- a/site/docs/skylark/backward-compatibility.md
+++ b/site/docs/skylark/backward-compatibility.md
@@ -53,6 +53,8 @@
flags](#disable-depsets-in-c-toolchain-api-in-user-flags)
* [Disallow using CROSSTOOL to select the cc_toolchain label](#disallow-using-crosstool-to-select-the-cc_toolchain-label)
* [Disallow using C++ Specific Make Variables from the configuration](#disallow-using-c-specific-make-variables-from-the-configuration)
+* [Disable legacy C++ configuration API](#disable-legacy-c-configuration-api)
+* [Disable legacy C++ toolchain API](#disable-legacy-c-toolchain-api)
### Dictionary concatenation
@@ -662,5 +664,163 @@
* Default: `false`
* Introduced in: `0.18.0`
-<!-- Add new options here -->
+### Disable legacy C++ configuration API
+This turns off legacy Starlark access to cc toolchain information via the
+`ctx.fragments.cpp` fragment. Instead of declaring dependency on the `ctx.fragments.cpp` using the
+`fragments` attribute declare a dependency on the `@bazel_tools//tools/cpp:current_cc_toolchain`
+via implicit attribute named `_cc_toolchain` (see example below). Use `find_cpp_toolchain` from
+`@bazel_tools//tools/cpp:toolchain_utils.bzl` to get the current C++ toolchain in the rule
+ implementation.
+
+```python
+# Before
+def _impl(ctx):
+ ...
+ ctx.fragments.cpp.compiler_options()
+
+foo = rule(
+ implementation = _impl,
+ fragments = ["cpp"],
+ ...
+)
+
+# After
+load("@bazel_tools//tools/cpp:toolchain_utils.bzl", "find_cpp_toolchain")
+
+def _impl(ctx):
+ ...
+ cc_toolchain = find_cpp_toolchain(ctx)
+ cc_toolchain.compiler_options()
+
+foo = rule(
+ implementation = _impl,
+ attrs = {
+ "_cc_toolchain": attr.label(
+ default=Label("@bazel_tools//tools/cpp:current_cc_toolchain")
+ ),
+ },
+)
+```
+
+List of all legacy fields and their corresponding `cc_toolchain` alternative:
+
+|`ctx.fragments.cpp` | `cc_toolchain` |
+|---|---|
+| `ar_executable` | `ar_executable()` |
+| `built_in_include_directories` | `built_in_include_directories` |
+| `c_options` | `c_options()` |
+| `compiler` | `compiler` |
+| `compiler_executable` | `compiler_executable()` |
+| `compiler_options(unused_arg)` | `compiler_options()` |
+| `cpu` | `cpu` |
+| `cxx_options(unused_arg)` | `cxx_options()` |
+| `dynamic_link_options(unused_arg, bool)` | `dynamic_link_options(bool)` |
+| `fully_static_link_options(unused_arg, True)` | `fully_static_link_options(True)` |
+| `ld_executable` | `ld_executable()` |
+| `link_options` | `link_options_do_not_use` |
+| `mostly_static_link_options(unused_arg, bool)` | `mostly_static_link_options(bool)` |
+| `nm_executable` | `nm_executable()` |
+| `objcopy_executable` | `objcopy_executable()` |
+| `objdump_executable` | `objdump_executable()` |
+| `preprocessor_executable` | `preprocessor_executable()` |
+| `strip_executable` | `strip_executable()` |
+| `sysroot` | `sysroot` |
+| `target_gnu_system_name` | `target_gnu_system_name` |
+| `unfiltered_compiler_options(unused_arg)` | `unfiltered_compiler_options(unused_arg)` |
+
+* Flag: `--incompatible_disable_legacy_cpp_toolchain_skylark_api`
+* Default: `false`
+* Introduced in: `0.18.0`
+
+### Disable legacy C++ toolchain API
+
+We have deprecated the `cc_toolchain` Starlark API returning legacy CROSSTOOL fields:
+
+* ar_executable
+* c_options
+* compiler_executable
+* compiler_options
+* cxx_options
+* dynamic_link_options
+* fully_static_link_options
+* ld_executable
+* link_options
+* mostly_static_link_options
+* nm_executable
+* objcopy_executable
+* objdump_executable
+* preprocessor_executable
+* strip_executable
+* unfiltered_compiler_options
+
+Use the new API from [cc_common](https://docs.bazel.build/versions/master/skylark/lib/cc_common.html)
+
+```python
+# Before:
+load("@bazel_tools//tools/cpp:toolchain_utils.bzl", "find_cpp_toolchain")
+
+def _impl(ctx):
+ cc_toolchain = find_cc_toolchain(ctx)
+ compiler_options = (
+ cc_toolchain.compiler_options() +
+ cc_toolchain.unfiltered_compiler_options([]) +
+ ["-w", "-Wno-error"]
+ )
+ link_options = (
+ ["-shared", "-static-libgcc"] +
+ cc_toolchain.mostly_static_link_options(True) +
+ ["-Wl,-whole-archive"] +
+ [l.path for l in libs] +
+ ["-Wl,-no-whole-archive"] +
+ cc_toolchain.link_options_do_not_use
+ )
+
+# After
+load("@bazel_tools//tools/cpp:toolchain_utils.bzl", "find_cpp_toolchain")
+load(
+ "@bazel_tools//tools/build_defs/cc:action_names.bzl",
+ "CPP_LINK_DYNAMIC_LIBRARY_ACTION_NAME",
+ "C_COMPILE_ACTION_NAME",
+)
+
+def _impl(ctx):
+ cc_toolchain = find_cc_toolchain(ctx)
+ feature_configuration = cc_common.configure_features(
+ cc_toolchain = cc_toolchain,
+ requested_features = ctx.features,
+ unsupported_features = ctx.disabled_features,
+ )
+ compile_variables = cc_common.create_compile_variables(
+ feature_configuration = feature_configuration,
+ cc_toolchain = cc_toolchain,
+ user_compile_flags = depset(["-w", "-Wno-error"]),
+ )
+ compiler_options = cc_common.get_memory_inefficient_command_line(
+ feature_configuration = feature_configuration,
+ action_name = C_COMPILE_ACTION_NAME,
+ variables = compile_variables,
+ )
+
+ link_variables = cc_common.create_link_variables(
+ feature_configuration = feature_configuration,
+ cc_toolchain = cc_toolchain,
+ is_linking_dynamic_library = True,
+ user_link_flags =
+ ["-static-libgcc"] +
+ ["-Wl,-whole-archive"] +
+ [lib.path for lib in libs] +
+ ["-Wl,-no-whole-archive"],
+ )
+ link_flags = cc_common.get_memory_inefficient_command_line(
+ feature_configuration = feature_configuration,
+ action_name = CPP_LINK_DYNAMIC_LIBRARY_ACTION_NAME,
+ variables = link_variables,
+ )
+```
+
+* Flag: `--incompatible_disable_legacy_flags_cc_toolchain_api`
+* Default: `false`
+* Introduced in: `0.19.0`
+
+<!-- Add new options here -->
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java
index 3bbcfeb..32255c5 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java
@@ -1212,25 +1212,34 @@
null,
"Information about the C++ toolchain API is not accessible "
+ "anymore through ctx.fragments.cpp "
- + "(See --incompatible_disable_legacy_cpp_toolchain_skylark_api). "
+ + "(see --incompatible_disable_legacy_cpp_toolchain_skylark_api on "
+ + "http://docs.bazel.build/versions/master/skylark/backward-compatibility.html"
+ + "#disable-legacy-c-configuration-api for migration notes). "
+ "Use CcToolchainInfo instead.");
}
}
public void checkForLegacyCompilationApiAvailability() throws EvalException {
- if (cppOptions.disableLegacyCompilationApi) {
+ if (cppOptions.disableLegacyCompilationApi || cppOptions.disableLegacyFlagsCcToolchainApi) {
throw new EvalException(
null,
"Skylark APIs accessing compilation flags has been removed. "
- + "Use the new API on cc_common.");
+ + "Use the new API on cc_common (see "
+ + "--incompatible_disable_legacy_flags_cc_toolchain_api on"
+ + "https://docs.bazel.build/versions/master/skylark/backward-compatibility.html"
+ + "#disable-legacy-c-toolchain-api for migration notes).");
}
}
public void checkForLegacyLinkingApiAvailability() throws EvalException {
- if (cppOptions.disableLegacyLinkingApi) {
+ if (cppOptions.disableLegacyLinkingApi || cppOptions.disableLegacyFlagsCcToolchainApi) {
throw new EvalException(
null,
- "Skylark APIs accessing linking flags has been removed. Use the new API on cc_common.");
+ "Skylark APIs accessing linking flags has been removed. "
+ + "Use the new API on cc_common (see "
+ + "--incompatible_disable_legacy_flags_cc_toolchain_api on"
+ + "https://docs.bazel.build/versions/master/skylark/backward-compatibility.html"
+ + "#disable-legacy-c-toolchain-api for migration notes).");
}
}
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppOptions.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppOptions.java
index 2edf165..b18333c 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppOptions.java
@@ -776,7 +776,7 @@
OptionMetadataTag.INCOMPATIBLE_CHANGE,
OptionMetadataTag.TRIGGERED_BY_ALL_INCOMPATIBLE_CHANGES
},
- help = "Flag for disabling access to the C++ toolchain API through the ctx.fragments.cpp .")
+ help = "Flag for disabling access to the C++ toolchain API through the ctx.fragments.cpp.")
public boolean disableLegacyToolchainSkylarkApi;
@Option(
@@ -798,6 +798,20 @@
public boolean disableLegacyCompilationApi;
@Option(
+ name = "incompatible_disable_legacy_flags_cc_toolchain_api",
+ defaultValue = "false",
+ documentationCategory = OptionDocumentationCategory.UNDOCUMENTED,
+ effectTags = {OptionEffectTag.LOADING_AND_ANALYSIS},
+ metadataTags = {
+ OptionMetadataTag.INCOMPATIBLE_CHANGE,
+ OptionMetadataTag.TRIGGERED_BY_ALL_INCOMPATIBLE_CHANGES
+ },
+ help =
+ "Flag for disabling the legacy cc_toolchain Skylark API for accessing legacy "
+ + "CROSSTOOL fields.")
+ public boolean disableLegacyFlagsCcToolchainApi;
+
+ @Option(
name = "experimental_disable_linking_mode_flags",
defaultValue = "false",
documentationCategory = OptionDocumentationCategory.TOOLCHAIN,
@@ -822,7 +836,7 @@
effectTags = {OptionEffectTag.LOADING_AND_ANALYSIS},
metadataTags = {OptionMetadataTag.EXPERIMENTAL},
help =
- "If true, Bazel will not read crosstool flags from legacy crosstool fields (see #5187.")
+ "If true, Bazel will not read crosstool flags from legacy crosstool fields (see #5187).")
public boolean disableLegacyCrosstoolFields;
@Option(
diff --git a/src/test/java/com/google/devtools/build/lib/rules/cpp/CcToolchainProviderTest.java b/src/test/java/com/google/devtools/build/lib/rules/cpp/CcToolchainProviderTest.java
index 6d4f41d..9ee61dd 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/cpp/CcToolchainProviderTest.java
+++ b/src/test/java/com/google/devtools/build/lib/rules/cpp/CcToolchainProviderTest.java
@@ -15,7 +15,6 @@
package com.google.devtools.build.lib.rules.cpp;
import static com.google.common.truth.Truth.assertThat;
-import static com.google.devtools.build.lib.testutil.MoreAsserts.assertThrows;
import com.google.common.collect.ImmutableList;
import com.google.devtools.build.lib.analysis.ConfiguredTarget;
@@ -145,7 +144,13 @@
private void testDisablingLinkingApiMethod(String method) throws Exception {
useConfiguration("--experimental_disable_legacy_cc_linking_api");
- scratch.file(
+ testDisablingLinkingApiMethodWithConfiguration(method);
+ useConfiguration("--incompatible_disable_legacy_flags_cc_toolchain_api");
+ testDisablingLinkingApiMethodWithConfiguration(method);
+ }
+
+ private void testDisablingLinkingApiMethodWithConfiguration(String method) throws Exception {
+ scratch.overwriteFile(
"test/rule.bzl",
"def _impl(ctx):",
" provider = ctx.attr._cc_toolchain[cc_common.CcToolchainInfo]",
@@ -158,18 +163,15 @@
" fragments = [ 'cpp' ],",
" attrs = {'_cc_toolchain': attr.label(default=Label('//test:toolchain')) }",
")");
- scratch.file(
+ scratch.overwriteFile(
"test/BUILD",
"load(':rule.bzl', 'my_rule')",
"cc_toolchain_alias(name = 'toolchain')",
"my_rule(name = 'target')");
- AssertionError e =
- assertThrows(AssertionError.class, () -> getConfiguredTarget("//test:target"));
- assertThat(e)
- .hasMessageThat()
- .contains(
- "Skylark APIs accessing linking flags has been removed. "
- + "Use the new API on cc_common.");
+ invalidatePackages();
+ reporter.removeHandler(failFastHandler);
+ getConfiguredTarget("//test:target");
+ assertContainsEvent("Skylark APIs accessing linking flags has been removed.");
}
@Test
@@ -214,7 +216,13 @@
private void testDisablingCompilationApiMethod(String method) throws Exception {
useConfiguration("--experimental_disable_legacy_cc_compilation_api");
- scratch.file(
+ testDisablingCompilationApiMethodWithConfiguration(method);
+ useConfiguration("--incompatible_disable_legacy_flags_cc_toolchain_api");
+ testDisablingCompilationApiMethodWithConfiguration(method);
+ }
+
+ private void testDisablingCompilationApiMethodWithConfiguration(String method) throws Exception {
+ scratch.overwriteFile(
"test/rule.bzl",
"def _impl(ctx):",
" provider = ctx.attr._cc_toolchain[cc_common.CcToolchainInfo]",
@@ -227,18 +235,15 @@
" fragments = [ 'cpp' ],",
" attrs = {'_cc_toolchain': attr.label(default=Label('//test:toolchain')) }",
")");
- scratch.file(
+ scratch.overwriteFile(
"test/BUILD",
"load(':rule.bzl', 'my_rule')",
"cc_toolchain_alias(name = 'toolchain')",
"my_rule(name = 'target')");
- AssertionError e =
- assertThrows(AssertionError.class, () -> getConfiguredTarget("//test:target"));
- assertThat(e)
- .hasMessageThat()
- .contains(
- "Skylark APIs accessing compilation flags has been removed. "
- + "Use the new API on cc_common.");
+ invalidatePackages();
+ reporter.removeHandler(failFastHandler);
+ getConfiguredTarget("//test:target");
+ assertContainsEvent("Skylark APIs accessing compilation flags has been removed.");
}
@Test
