No need for exec_compatible_with now

haskell.bzl

@@ -102,36 +102,6 @@ _BUILD_MODE_PREFERRED_LINKAGE = select({
     }),
 })
 
-# Makes a build-time/test-time tool referenced via exec_dep or a
-# `$(exe ...)` string-parameter macro (e.g. glean-clang's clang-index,
-# glean-lang-haskell's hie-indexer - both invoked this way from
-# haskell_test()'s `test_args`, see buck2/platforms/BUCK) inherit the
-# *calling* target's own ambient `-m opt`/dev build mode, rather than
-# always landing on whichever execution platform happens to be first in
-# `.buckconfig`'s `[build] execution_platforms` list regardless of it.
-#
-# Execution-platform selection for an edge is driven by the *requesting*
-# target's own `exec_compatible_with` attribute (evaluated under that
-# target's own *ordinary*, non-exec configuration - so a select() here
-# keyed the usual way correctly sees the real ambient build mode), which
-# filters the globally-registered platform list down to ones providing
-# every listed constraint value. Setting this unconditionally on
-# clang-index/hie-indexer's own targets wouldn't work: those targets
-# themselves aren't what's being exec-configured here, the *referencing*
-# haskell_test() is - exec_compatible_with has to live there instead, so
-# it's applied via haskell_binary()/haskell_test() below rather than
-# left for each `$(exe ...)`-using BUCK file to remember individually.
-# In `dev`/default mode this resolves to `[]` (no requirement beyond
-# what's already implicit), keeping the existing `:exec-default`
-# resolution; in `opt` mode it requires `root//buck2/constraints:opt`,
-# which only `:exec-opt` provides, so opt builds now correctly get an
-# opt-mode clang-index/hie-indexer too instead of always getting a dev-
-# mode one.
-_BUILD_MODE_EXEC_COMPATIBLE_WITH = select({
-    "root//buck2/constraints:opt": ["root//buck2/constraints:opt"],
-    "DEFAULT": [],
-})
-
 # The `-dynamic-too`/native-shared-libs-symlink-tree machinery this
 # section used to force on unconditionally (via a `dynamic_too = True`
 # kwarg here) is now driven entirely by `haskell_toolchain.dynamic_ghc`
@@ -340,7 +310,6 @@ def haskell_binary(
     all_deps = deps + _package_deps(packages)
     kwargs.setdefault("link_style", _BUILD_MODE_LINK_STYLE)
     kwargs.setdefault("enable_profiling", _PROF_ENABLED)
-    kwargs.setdefault("exec_compatible_with", _BUILD_MODE_EXEC_COMPATIBLE_WITH)
     native.haskell_binary(
         name = name,
         srcs = _resolve_srcs(name, srcs, all_deps, hsc_flags),
@@ -404,14 +373,4 @@ def haskell_test(name, test_args = [], test_env = {}, cwd = None, **kwargs):
         test = test_target,
         args = args,
         env = {"LANG": "C.UTF-8"} | test_env,
-        # `args`'s own `$(exe ...)` macros (the cd-wrapper case just
-        # above, or test_args' own e.g. clang-index, hie-indexer - see
-        # buck2/platforms/BUCK) are resolved for *this* target, not the
-        # `:bin` haskell_binary() above - it's this sh_test() whose own
-        # exec_compatible_with governs which execution platform those
-        # tools get built under, so the same build-mode-inheriting
-        # default needs to be set here too, not just on haskell_binary()
-        # (which already gets it via its own kwargs.setdefault, but
-        # that's a separate target from this one).
-        exec_compatible_with = _BUILD_MODE_EXEC_COMPATIBLE_WITH,
     )