Split user_link_flags from legacy_link_flags

The difference between them is that user_link_flags will stay after we remove
legacy fields from the crosstool.

RELNOTES: None.
PiperOrigin-RevId: 196940832

3 files changed, 27 insertions, 5 deletions

diff --git a/tools/cpp/CROSSTOOL.tpl b/tools/cpp/CROSSTOOL.tpl
index b4d9edd713..38df97f323 100644
--- a/tools/cpp/CROSSTOOL.tpl
+++ b/tools/cpp/CROSSTOOL.tpl
@@ -378,6 +378,7 @@ toolchain {
     implies: 'linkstamps'
     implies: 'output_execpath_flags'
     implies: 'input_param_flags'
+    implies: 'user_link_flags'
     implies: 'legacy_link_flags'
     implies: 'linker_subsystem_flag'
     implies: 'linker_param_file'
@@ -397,6 +398,7 @@ toolchain {
     implies: 'linkstamps'
     implies: 'output_execpath_flags'
     implies: 'input_param_flags'
+    implies: 'user_link_flags'
     implies: 'legacy_link_flags'
     implies: 'linker_subsystem_flag'
     implies: 'linker_param_file'
@@ -418,6 +420,7 @@ toolchain {
       implies: 'linkstamps'
       implies: 'output_execpath_flags'
       implies: 'input_param_flags'
+      implies: 'user_link_flags'
       implies: 'legacy_link_flags'
       implies: 'linker_subsystem_flag'
       implies: 'linker_param_file'
@@ -738,8 +741,8 @@ toolchain {
   }
 
   # Since this feature is declared earlier in the CROSSTOOL than
-  # "legacy_link_flags", this feature will be applied prior to it anwyhere they
-  # are both implied. And since "legacy_link_flags" contains the linkopts from
+  # "user_link_flags", this feature will be applied prior to it anwyhere they
+  # are both implied. And since "user_link_flags" contains the linkopts from
   # the build rule, this allows the user to override the /SUBSYSTEM in the BUILD
   # file.
   feature {
@@ -754,11 +757,24 @@ toolchain {
     }
   }
 
-  # The "legacy_link_flags" may contain user-defined linkopts (from build rules)
+  # The "user_link_flags" contains user-defined linkopts (from build rules)
   # so it should be defined after features that declare user-overridable flags.
   # For example the "linker_subsystem_flag" defines a default "/SUBSYSTEM" flag
   # but we want to let the user override it, therefore "link_flag_subsystem" is
-  # defined earlier in the CROSSTOOL file than "legacy_link_flags".
+  # defined earlier in the CROSSTOOL file than "user_link_flags".
+  feature {
+    name: 'user_link_flags'
+    flag_set {
+      expand_if_all_available: 'user_link_flags'
+      action: 'c++-link-executable'
+      action: 'c++-link-dynamic-library'
+      action: "c++-link-nodeps-dynamic-library"
+      flag_group {
+        iterate_over: 'user_link_flags'
+        flag: '%{user_link_flags}'
+      }
+    }
+  }
   feature {
     name: 'legacy_link_flags'
     flag_set {
diff --git a/tools/cpp/crosstool_lib.bzl b/tools/cpp/crosstool_lib.bzl
index 1ddd838d0a..a6c4916947 100644
--- a/tools/cpp/crosstool_lib.bzl
+++ b/tools/cpp/crosstool_lib.bzl
@@ -158,6 +158,12 @@ def get_features_to_appear_first(platform):
           ["-pie"],
           expand_if_all_available=["force_pic"]),
       simple_feature(
+          "user_link_flags",
+          LINK_ACTIONS,
+          ["%{user_link_flags}"],
+          iterate_over="user_link_flags",
+          expand_if_all_available=["user_link_flags"]),
+      simple_feature(
           "legacy_link_flags",
           LINK_ACTIONS,
           ["%{legacy_link_flags}"],
diff --git a/tools/cpp/crosstool_utils.bzl b/tools/cpp/crosstool_utils.bzl
index 06bfc63202..238d0cff6d 100644
--- a/tools/cpp/crosstool_utils.bzl
+++ b/tools/cpp/crosstool_utils.bzl
@@ -31,9 +31,9 @@ COMPILE_ACTIONS = [
 
 # All possible C++ link actions
 LINK_ACTIONS = [
+    "c++-link-executable",
     "c++-link-dynamic-library",
     "c++-link-nodeps-dynamic-library",
-    "c++-link-executable",
 ]
 
 # All possible C++ archive actions