take advantage of XMake runtimes support

2 files changed, 32 insertions, 76 deletions

diff --git a/xmake/rules/c++/modules/modules_support/clang/compiler_support.lua b/xmake/rules/c++/modules/modules_support/clang/compiler_support.lua
index a1f10b5ae..95578acee 100644
--- a/xmake/rules/c++/modules/modules_support/clang/compiler_support.lua
+++ b/xmake/rules/c++/modules/modules_support/clang/compiler_support.lua
@@ -34,8 +34,11 @@ function _get_toolchain_includedirs_for_stlheaders(target, includedirs, clang)
     local tmpfile = os.tmpfile() .. ".cc"
     io.writefile(tmpfile, "#include <vector>")
     local argv = {"-E", "-x", "c++", tmpfile}
-    if _use_stdlib(target, "libc++") then
+    local runtime = get_cpplibrary_name(target)
+    if runtime:startswith("c++") then
         table.insert(argv, 1, "-stdlib=libc++")
+    elseif runtime:startswith("stdc++") then
+        table.insert(argv, 1, "-stdlib=libstdc++")
     end
     local result = try {function () return os.iorunv(clang, argv) end}
     if result then
@@ -53,16 +56,20 @@ function _get_toolchain_includedirs_for_stlheaders(target, includedirs, clang)
     os.tryrm(tmpfile)
 end
 
--- use the given stdlib? e.g. libc++ or libstdc++
-function _use_stdlib(target, name)
-    local default = "libstdc++"
-    if is_plat("windows") then
-        default = "msstl"
-    elseif is_plat("macos") then
-        default = "libc++"
+function get_cpplibrary_name(target)
+    local runtime = target:runtimes()
+
+    if not runtime then
+        if is_plat("windows") then
+            runtime = "msstl"
+        elseif is_plat("linux") or is_plat("android") then
+            runtime = "stdc++_shared"
+        elseif is_plat("macosx") or is_plat("iphoneos") or is_plat("watchos") then
+            runtime = "c++_shared"
+        end
     end
-    local stdlib = target:data("cxx.modules.stdlib") or default
-    return stdlib == name
+
+    return runtime
 end
 
 -- load module support for the current target
@@ -93,19 +100,6 @@ function load(target)
         target:set("symbols", dep_symbols and dep_symbols or "none")
     end
 
-    -- if use libc++, we need to install libc++ and libc++abi
-    --
-    -- on ubuntu:
-    -- sudo apt install libc++-dev libc++abi-15-dev
-    --
-    local flags = table.join(target:get("cxxflags") or {}, get_config("cxxflags") or {})
-    if table.contains(flags, "-stdlib=libc++", "clang::-stdlib=libc++") then
-        target:data_set("cxx.modules.stdlib", "libc++")
-    elseif table.contains(flags, "-stdlib=libstdc++", "clang::-stdlib=libstdc++") then
-        target:data_set("cxx.modules.stdlib", "libstdc++")
-    end
-    set_stdlib_flags(target)
-
     -- on Windows before llvm18 we need to disable delayed-template-parsing because it's incompatible with modules, from llvm >= 18, it's disabled by default
     local clang_version = get_clang_version(target)
     if semver.compare(clang_version, "18") < 0 then
@@ -121,7 +115,14 @@ function toolchain_includedirs(target)
         local clang, toolname = target:tool("cxx")
         assert(toolname:startswith("clang"))
         _get_toolchain_includedirs_for_stlheaders(target, includedirs, clang)
-        local _, result = try {function () return os.iorunv(clang, {"-E", "-stdlib=libc++", "-Wp,-v", "-xc", os.nuldev()}) end}
+        local runtime = get_cpplibrary_name(target)
+        local runtime_flag
+        if runtime:startswith("c++") then
+            runtime_flag = "-stdlib=libc++"
+        elseif runtime:startswith("stdc++") then
+            runtime_flag = "-stdlib=libstdc++"
+        end
+        local _, result = try {function () return os.iorunv(clang, {"-E", runtime_flag, "-Wp,-v", "-xc", os.nuldev()}) end}
         if result then
             for _, line in ipairs(result:split("\n", {plain = true})) do
                 line = line:trim()
@@ -195,24 +196,16 @@ function get_clang_scan_deps(target)
     return clang_scan_deps or nil
 end
 
--- set stdlib flags, it will use libstdc++ if we do not set `-stdlib=`
-function set_stdlib_flags(target)
-    if _use_stdlib(target, "libc++") then
-        target:add("cxxflags", "-stdlib=libc++")
-        target:add("ldflags", "-stdlib=libc++")
-        target:add("shflags", "-stdlib=libc++")
-    end
-end
-
 -- not supported atm
 function get_stdmodules(target)
     if target:policy("build.c++.modules.std") then
-        if _use_stdlib(target, "libc++") then
+        local runtime = get_cpplibrary_name(target)
+
+        if runtime:startswith("libc++") then
             -- TODO support libc++ std module file when https://github.com/xmake-io/xmake/pull/4630
-            return {}
-        elseif _use_stdlib(target, "libstdc++") then
+        elseif runtime:startswith("stdc++") then
             -- libstdc++ doesn't have a std module file atm
-        elseif _use_stdlib(target, "msstl") then
+        elseif runtime:startswith("msstl") then
             -- msstl std module file is not compatible with llvm <= 18
             -- local toolchain = target:toolchain("clang")
             -- local msvc = import("core.tool.toolchain", {anonymous = true}).load("msvc", {plat = toolchain:plat(), arch = toolchain:arch()})
diff --git a/xmake/rules/c++/modules/modules_support/clang/dependency_scanner.lua b/xmake/rules/c++/modules/modules_support/clang/dependency_scanner.lua
index 7ad037f99..71ccabb72 100644
--- a/xmake/rules/c++/modules/modules_support/clang/dependency_scanner.lua
+++ b/xmake/rules/c++/modules/modules_support/clang/dependency_scanner.lua
@@ -47,10 +47,9 @@ function generate_dependencies(target, sourcebatch, opt)
                     clang_path = compiler_support.get_clang_path(target) or compinst:program()
                 end
                 local clangscandeps = compiler_support.get_clang_scan_deps(target)
-                local compinst = target:compiler("cxx")
                 local compflags = compinst:compflags({sourcefile = sourcefile, target = target})
                 local flags = table.join({"--format=p1689", "--",
-                                         clang_path, "-x", "c++", "-c", sourcefile, "-o", target:objectfile(sourcefile)}, compflags or {})
+                                         clang_path, "-x", "c++", runtime_flag, "-c", sourcefile, "-o", target:objectfile(sourcefile)}, compflags or {})
                 vprint(table.concat(table.join(clangscandeps, flags), " "))
                 local outdata, errdata = os.iorunv(clangscandeps, flags)
                 assert(errdata, errdata)
@@ -65,7 +64,7 @@ function generate_dependencies(target, sourcebatch, opt)
                         return flag:startswith("-fmodule") or flag:startswith("-std=c++") or flag:startswith("-std=gnu++")
                     end)
                     local ifile = path.translate(path.join(outputdir, path.filename(file) .. ".i"))
-                    local flags = table.join(compflags or {}, {"-E", "-fkeep-system-includes", "-x", "c++", file, "-o", ifile})
+                    local flags = table.join(compflags or {}, {"-E", runtime_flag, "-fkeep-system-includes", "-x", "c++", file, "-o", ifile})
                     os.vrunv(compinst:program(), flags)
                     local content = io.readfile(ifile)
                     os.rm(ifile)
@@ -75,44 +74,8 @@ function generate_dependencies(target, sourcebatch, opt)
             changed = true
 
             local rawdependinfo = io.readfile(jsonfile)
-            if rawdependinfo then
-                local dependinfo = json.decode(rawdependinfo)
-                if target:data("cxx.modules.stdlib") == nil then
-                    local has_std_modules = false
-                    for _, r in ipairs(dependinfo.rules) do
-                        for _, required in ipairs(r.requires) do
-                            -- it may be `std:utility`, ..
-                            -- @see https://github.com/xmake-io/xmake/issues/3373
-                            local logical_name = required["logical-name"]
-                            if logical_name and (logical_name == "std" or logical_name:startswith("std.") or logical_name:startswith("std:")) then
-                                has_std_modules = true
-                                break
-                            end
-                        end
-
-                        if has_std_modules then
-                            break
-                        end
-                    end
-                    if has_std_modules then
-
-                        -- we need clang >= 17.0 or use clang stdmodules if the current target contains std module
-                        local clang_version = compiler_support.get_clang_version(target)
-                        assert((clang_version and semver.compare(clang_version, "17.0") >= 0) or target:policy("build.c++.clang.stdmodules"),
-                               [[On llvm <= 16 standard C++ modules are not supported ;
-                               they can be emulated through clang modules and supported only on libc++ ;
-                               please add -stdlib=libc++ cxx flag or disable strict mode]])
-
-                        -- we use libc++ by default if we do not explicitly specify -stdlib:libstdc++
-                        target:data_set("cxx.modules.stdlib", "libc++")
-                        compiler_support.set_stdlib_flags(target)
-                    end
-                end
-            end
-
             return {moduleinfo = rawdependinfo}
         end, {dependfile = dependfile, files = {sourcefile}, changed = target:is_rebuilt()})
     end
     return changed
 end
-