1 files changed, 26 insertions, 0 deletions
diff --git a/xmake/rules/c++/modules/clang/support.lua b/xmake/rules/c++/modules/clang/support.lua
index 71bd2e735..a010fdde1 100644
--- a/xmake/rules/c++/modules/clang/support.lua
+++ b/xmake/rules/c++/modules/clang/support.lua
@@ -130,6 +130,13 @@ function has_two_phase_compilation_support(target)
     return target:policy("build.c++.modules.two_phases")
 end
 
+function has_precompile_reduced_bmi_support(target)
+    if not target:policy("build.c++.modules.clang.precompile_reduced_bmi") or not has_two_phase_compilation_support(target) then
+        return false
+    end
+    return get_modulesprecompilereducedbmiflag(target) ~= nil
+end
+
 -- flags that doesn't affect bmi generation
 function strippeable_flags()
     -- speculative list as there is no resource that list flags that prevent reusability, this list will likely be improve over time
@@ -411,6 +418,25 @@ function get_modulesreducedbmiflag(target)
     return modulesreducedbmiflag or nil
 end
 
+function get_modulesprecompilereducedbmiflag(target)
+    local modulesprecompilereducedbmiflag = _g.modulesprecompilereducedbmiflag
+    if modulesprecompilereducedbmiflag == nil then
+        local compinst = target:compiler("cxx")
+        local checkflags = "--precompile-reduced-bmi"
+        if target:has_tool("cxx", "clang_cl") then
+            -- clang_cl.has_flags() appends -c and treats unused-argument warnings as errors,
+            -- but --precompile-reduced-bmi does not use -c. Ignore that specific warning and
+            -- treat unknown-argument warnings as errors to reject unsupported flags.
+            checkflags = {checkflags, "-Wno-unused-command-line-argument", "-Werror=unknown-argument"}
+        end
+        if compinst:has_flags(checkflags, "cxxflags", {flagskey = "clang_modules_precompile_reduced_bmi", tryrun = true}) then
+            modulesprecompilereducedbmiflag = "--precompile-reduced-bmi"
+        end
+        _g.modulesprecompilereducedbmiflag = modulesprecompilereducedbmiflag or false
+    end
+    return modulesprecompilereducedbmiflag or nil
+end
+
 function has_clangscandepssupport(target)
     local support_clangscandeps = _g.support_clangscandeps
     if support_clangscandeps == nil then