Allow removal of default cc flags

This PR modifies the cc toolchain logic so that users can remove (most of) the default compile/linker flags if they so wish. This is required when building 3rd party projects, e.g. Qt, using Bazel.

Closes #14735.

PiperOrigin-RevId: 471502084
Change-Id: Idbc3e6685bc10c6b51fdff7ab7839dc9e00a5209

Author: jheaff1

src/main/java/com/google/devtools/build/lib/rules/cpp/CcCommon.java

@@ -1050,22 +1050,6 @@ public static FeatureConfiguration configureFeaturesOrThrowEvalException(
 
     ImmutableSet<String> allUnsupportedFeatures = unsupportedFeaturesBuilder.build();
 
-    // If STATIC_LINK_MSVCRT feature isn't specified by user, we add DYNAMIC_LINK_MSVCRT_* feature
-    // according to compilation mode.
-    // If STATIC_LINK_MSVCRT feature is specified, we add STATIC_LINK_MSVCRT_* feature
-    // according to compilation mode.
-    if (requestedFeatures.contains(CppRuleClasses.STATIC_LINK_MSVCRT)) {
-      allRequestedFeaturesBuilder.add(
-          cppConfiguration.getCompilationMode() == CompilationMode.DBG
-              ? CppRuleClasses.STATIC_LINK_MSVCRT_DEBUG
-              : CppRuleClasses.STATIC_LINK_MSVCRT_NO_DEBUG);
-    } else {
-      allRequestedFeaturesBuilder.add(
-          cppConfiguration.getCompilationMode() == CompilationMode.DBG
-              ? CppRuleClasses.DYNAMIC_LINK_MSVCRT_DEBUG
-              : CppRuleClasses.DYNAMIC_LINK_MSVCRT_NO_DEBUG);
-    }
-
     ImmutableList.Builder<String> allFeatures =
         new ImmutableList.Builder<String>()
             .addAll(ImmutableSet.of(cppConfiguration.getCompilationMode().toString()))

tools/cpp/windows_cc_toolchain_config.bzl

@@ -21,7 +21,6 @@ load(
     "env_entry",
     "env_set",
     "feature",
-    "feature_set",
     "flag_group",
     "flag_set",
     "tool",
@@ -135,7 +134,6 @@ def _impl(ctx):
                 "output_execpath_flags",
                 "input_param_flags",
                 "user_link_flags",
-                "default_link_flags",
                 "linker_subsystem_flag",
                 "linker_param_file",
                 "msvc_env",
@@ -187,13 +185,11 @@ def _impl(ctx):
             implies = [
                 "compiler_input_flags",
                 "compiler_output_flags",
-                "default_compile_flags",
                 "nologo",
                 "msvc_env",
                 "parse_showincludes",
                 "user_compile_flags",
                 "sysroot",
-                "unfiltered_compile_flags",
             ],
             tools = [tool(path = ctx.attr.msvc_cl_path)],
         )
@@ -219,13 +215,11 @@ def _impl(ctx):
             implies = [
                 "compiler_input_flags",
                 "compiler_output_flags",
-                "default_compile_flags",
                 "nologo",
                 "msvc_env",
                 "parse_showincludes",
                 "user_compile_flags",
                 "sysroot",
-                "unfiltered_compile_flags",
             ],
             tools = [tool(path = ctx.attr.msvc_cl_path)],
         )
@@ -238,7 +232,6 @@ def _impl(ctx):
                 "output_execpath_flags",
                 "input_param_flags",
                 "user_link_flags",
-                "default_link_flags",
                 "linker_subsystem_flag",
                 "linker_param_file",
                 "msvc_env",
@@ -256,7 +249,6 @@ def _impl(ctx):
                 "output_execpath_flags",
                 "input_param_flags",
                 "user_link_flags",
-                "default_link_flags",
                 "linker_subsystem_flag",
                 "linker_param_file",
                 "msvc_env",
@@ -356,6 +348,7 @@ def _impl(ctx):
 
         unfiltered_compile_flags_feature = feature(
             name = "unfiltered_compile_flags",
+            enabled = True,
             flag_sets = [
                 flag_set(
                     actions = [
@@ -540,21 +533,57 @@ def _impl(ctx):
             ],
         )
 
-        static_link_msvcrt_feature = feature(name = "static_link_msvcrt")
+        static_link_msvcrt_feature = feature(
+            name = "static_link_msvcrt",
+            flag_sets = [
+                flag_set(
+                    actions = [ACTION_NAMES.c_compile, ACTION_NAMES.cpp_compile],
+                    flag_groups = [flag_group(flags = ["/MT"])],
+                    with_features = [with_feature_set(not_features = ["dbg"])],
+                ),
+                flag_set(
+                    actions = [ACTION_NAMES.c_compile, ACTION_NAMES.cpp_compile],
+                    flag_groups = [flag_group(flags = ["/MTd"])],
+                    with_features = [with_feature_set(features = ["dbg"])],
+                ),
+                flag_set(
+                    actions = all_link_actions,
+                    flag_groups = [flag_group(flags = ["/DEFAULTLIB:libcmt.lib"])],
+                    with_features = [with_feature_set(not_features = ["dbg"])],
+                ),
+                flag_set(
+                    actions = all_link_actions,
+                    flag_groups = [flag_group(flags = ["/DEFAULTLIB:libcmtd.lib"])],
+                    with_features = [with_feature_set(features = ["dbg"])],
+                ),
+            ],
+        )
 
-        dynamic_link_msvcrt_debug_feature = feature(
-            name = "dynamic_link_msvcrt_debug",
+        dynamic_link_msvcrt_feature = feature(
+            name = "dynamic_link_msvcrt",
+            enabled = True,
             flag_sets = [
+                flag_set(
+                    actions = [ACTION_NAMES.c_compile, ACTION_NAMES.cpp_compile],
+                    flag_groups = [flag_group(flags = ["/MD"])],
+                    with_features = [with_feature_set(not_features = ["dbg", "static_link_msvcrt"])],
+                ),
                 flag_set(
                     actions = [ACTION_NAMES.c_compile, ACTION_NAMES.cpp_compile],
                     flag_groups = [flag_group(flags = ["/MDd"])],
+                    with_features = [with_feature_set(features = ["dbg"], not_features = ["static_link_msvcrt"])],
+                ),
+                flag_set(
+                    actions = all_link_actions,
+                    flag_groups = [flag_group(flags = ["/DEFAULTLIB:msvcrt.lib"])],
+                    with_features = [with_feature_set(not_features = ["dbg", "static_link_msvcrt"])],
                 ),
                 flag_set(
                     actions = all_link_actions,
                     flag_groups = [flag_group(flags = ["/DEFAULTLIB:msvcrtd.lib"])],
+                    with_features = [with_feature_set(features = ["dbg"], not_features = ["static_link_msvcrt"])],
                 ),
             ],
-            requires = [feature_set(features = ["dbg"])],
         )
 
         dbg_feature = feature(
@@ -709,24 +738,6 @@ def _impl(ctx):
             ],
         )
 
-        dynamic_link_msvcrt_no_debug_feature = feature(
-            name = "dynamic_link_msvcrt_no_debug",
-            flag_sets = [
-                flag_set(
-                    actions = [ACTION_NAMES.c_compile, ACTION_NAMES.cpp_compile],
-                    flag_groups = [flag_group(flags = ["/MD"])],
-                ),
-                flag_set(
-                    actions = all_link_actions,
-                    flag_groups = [flag_group(flags = ["/DEFAULTLIB:msvcrt.lib"])],
-                ),
-            ],
-            requires = [
-                feature_set(features = ["fastbuild"]),
-                feature_set(features = ["opt"]),
-            ],
-        )
-
         disable_assertions_feature = feature(
             name = "disable_assertions",
             enabled = True,
@@ -791,24 +802,6 @@ def _impl(ctx):
             ],
         )
 
-        static_link_msvcrt_no_debug_feature = feature(
-            name = "static_link_msvcrt_no_debug",
-            flag_sets = [
-                flag_set(
-                    actions = [ACTION_NAMES.c_compile, ACTION_NAMES.cpp_compile],
-                    flag_groups = [flag_group(flags = ["/MT"])],
-                ),
-                flag_set(
-                    actions = all_link_actions,
-                    flag_groups = [flag_group(flags = ["/DEFAULTLIB:libcmt.lib"])],
-                ),
-            ],
-            requires = [
-                feature_set(features = ["fastbuild"]),
-                feature_set(features = ["opt"]),
-            ],
-        )
-
         treat_warnings_as_errors_feature = feature(
             name = "treat_warnings_as_errors",
             flag_sets = [
@@ -887,21 +880,6 @@ def _impl(ctx):
             ],
         )
 
-        static_link_msvcrt_debug_feature = feature(
-            name = "static_link_msvcrt_debug",
-            flag_sets = [
-                flag_set(
-                    actions = [ACTION_NAMES.c_compile, ACTION_NAMES.cpp_compile],
-                    flag_groups = [flag_group(flags = ["/MTd"])],
-                ),
-                flag_set(
-                    actions = all_link_actions,
-                    flag_groups = [flag_group(flags = ["/DEFAULTLIB:libcmtd.lib"])],
-                ),
-            ],
-            requires = [feature_set(features = ["dbg"])],
-        )
-
         frame_pointer_feature = feature(
             name = "frame_pointer",
             flag_sets = [
@@ -1105,10 +1083,7 @@ def _impl(ctx):
             default_link_flags_feature,
             linker_param_file_feature,
             static_link_msvcrt_feature,
-            static_link_msvcrt_no_debug_feature,
-            dynamic_link_msvcrt_no_debug_feature,
-            static_link_msvcrt_debug_feature,
-            dynamic_link_msvcrt_debug_feature,
+            dynamic_link_msvcrt_feature,
             dbg_feature,
             fastbuild_feature,
             opt_feature,