Index: clang/docs/ReleaseNotes.rst =================================================================== --- clang/docs/ReleaseNotes.rst +++ clang/docs/ReleaseNotes.rst @@ -119,6 +119,10 @@ Windows Support --------------- +- clang-cl now defaults to ``/Zc:twoPhase`` if targeting MSVC2017 update 3 or + later (``_MSC_VER`` >= 1911). This matches MSVC's behavior. Explicitly pass + ``/Zc:twoPhase-`` to restore the old behavior. + C Language Changes in Clang --------------------------- Index: clang/include/clang/Driver/Options.td =================================================================== --- clang/include/clang/Driver/Options.td +++ clang/include/clang/Driver/Options.td @@ -6008,10 +6008,10 @@ def _SLASH_Zc_trigraphs_off : CLFlag<"Zc:trigraphs-">, HelpText<"Disable trigraphs (default)">, Alias; def _SLASH_Zc_twoPhase : CLFlag<"Zc:twoPhase">, - HelpText<"Enable two-phase name lookup in templates">, + HelpText<"Enable two-phase name lookup in templates (default)">, Alias; def _SLASH_Zc_twoPhase_ : CLFlag<"Zc:twoPhase-">, - HelpText<"Disable two-phase name lookup in templates (default)">, + HelpText<"Disable two-phase name lookup in templates">, Alias; def _SLASH_Z7 : CLFlag<"Z7">, HelpText<"Enable CodeView debug information in object files">; Index: clang/lib/Driver/ToolChains/Clang.cpp =================================================================== --- clang/lib/Driver/ToolChains/Clang.cpp +++ clang/lib/Driver/ToolChains/Clang.cpp @@ -6124,12 +6124,14 @@ !IsWindowsMSVC || IsMSVC2015Compatible)) CmdArgs.push_back("-fno-threadsafe-statics"); - // -fno-delayed-template-parsing is default, except when targeting MSVC. - // Many old Windows SDK versions require this to parse. - // FIXME: MSVC introduced /Zc:twoPhase- to disable this behavior in their - // compiler. We should be able to disable this by default at some point. + // -fno-delayed-template-parsing is default, except when targeting MSVC + // earlier than MSVC 2017 15.3 (_MSC_VER 1911). Windows SDK versions + // 10.0.15063.0 (Creators Update or Redstone 2) and earlier require this to + // parse. + bool IsMSVCBefore2017Update3 = !MSVT.empty() && MSVT < VersionTuple(19, 11); if (Args.hasFlag(options::OPT_fdelayed_template_parsing, - options::OPT_fno_delayed_template_parsing, IsWindowsMSVC)) + options::OPT_fno_delayed_template_parsing, + IsMSVCBefore2017Update3)) CmdArgs.push_back("-fdelayed-template-parsing"); // -fgnu-keywords default varies depending on language; only pass if Index: clang/test/Driver/cl-options.c =================================================================== --- clang/test/Driver/cl-options.c +++ clang/test/Driver/cl-options.c @@ -329,13 +329,19 @@ // We recognize -f[no-]delayed-template-parsing. // /Zc:twoPhase[-] has the opposite meaning. -// RUN: %clang_cl -c -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDDEFAULT %s -// DELAYEDDEFAULT: "-fdelayed-template-parsing" -// RUN: %clang_cl -c -fdelayed-template-parsing -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDON %s -// RUN: %clang_cl -c /Zc:twoPhase- -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDON %s +// RUN: %clang_cl -c -fmsc-version=1910 -### -- %s 2>&1 | FileCheck -check-prefix=OLDDELAYEDDEFAULT %s +// OLDDELAYEDDEFAULT: "-fdelayed-template-parsing" +// RUN: %clang_cl -c -fmsc-version=1911 -### -- %s 2>&1 | FileCheck -check-prefix=NEWDELAYEDDEFAULT %s +// NEWDELAYEDDEFAULT-NOT: "-fdelayed-template-parsing" +// RUN: %clang_cl -c -fmsc-version=1910 -fdelayed-template-parsing -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDON %s +// RUN: %clang_cl -c -fmsc-version=1911 -fdelayed-template-parsing -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDON %s +// RUN: %clang_cl -c -fmsc-version=1910 /Zc:twoPhase- -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDON %s +// RUN: %clang_cl -c -fmsc-version=1911 /Zc:twoPhase- -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDON %s // DELAYEDON: "-fdelayed-template-parsing" -// RUN: %clang_cl -c -fno-delayed-template-parsing -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDOFF %s -// RUN: %clang_cl -c /Zc:twoPhase -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDOFF %s +// RUN: %clang_cl -c -fmsc-version=1910 -fno-delayed-template-parsing -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDOFF %s +// RUN: %clang_cl -c -fmsc-version=1911 -fno-delayed-template-parsing -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDOFF %s +// RUN: %clang_cl -c -fmsc-version=1910 /Zc:twoPhase -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDOFF %s +// RUN: %clang_cl -c -fmsc-version=1911 /Zc:twoPhase -### -- %s 2>&1 | FileCheck -check-prefix=DELAYEDOFF %s // DELAYEDOFF-NOT: "-fdelayed-template-parsing" // RUN: %clang_cl -c -### /std:c++latest -- %s 2>&1 | FileCheck -check-prefix CHECK-LATEST-CHAR8_T %s