diff --git a/clang/docs/UsersManual.rst b/clang/docs/UsersManual.rst
index ea75d1e2227a..32c6ac2270fe 100644
--- a/clang/docs/UsersManual.rst
+++ b/clang/docs/UsersManual.rst
@@ -2024,8 +2024,9 @@ with a warning. For example:
To suppress warnings about unused arguments, use the ``-Qunused-arguments`` option.
-Options that are not known to clang-cl will cause errors. If they are spelled with a
-leading ``/``, they will be mistaken for a filename:
+Options that are not known to clang-cl will be ignored by default. Use the
+``-Werror=unknown-argument`` option in order to treat them as errors. If these
+options are spelled with a leading ``/``, they will be mistaken for a filename:
::
diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
index b04498f3188c..1ba9e1464cdd 100644
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -93,6 +93,9 @@ def err_target_unsupported_arch
def err_drv_I_dash_not_supported : Error<
"'%0' not supported, please use -iquote instead">;
def err_drv_unknown_argument : Error<"unknown argument: '%0'">;
+def warn_drv_unknown_argument_clang_cl : Warning<
+ "unknown argument ignored in clang-cl: '%0'">,
+ InGroup<UnknownArgument>;
def err_drv_invalid_value : Error<"invalid value '%1' in '%0'">;
def err_drv_invalid_int_value : Error<"invalid integral value '%1' in '%0'">;
def err_drv_invalid_remap_file : Error<
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 41e7d2a85e1d..969050df5963 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -848,3 +848,5 @@ def FutureCompat : DiagGroup<"future-compat">;
def InvalidOrNonExistentDirectory : DiagGroup<"invalid-or-nonexistent-directory">;
def OptionIgnored : DiagGroup<"option-ignored">;
+
+def UnknownArgument : DiagGroup<"unknown-argument">;
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 5c01ef0bba7c..22eed5cab6f7 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -146,7 +146,9 @@ InputArgList Driver::ParseArgStrings(ArrayRef<const char *> ArgStrings) {
}
for (const Arg *A : Args.filtered(options::OPT_UNKNOWN))
- Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(Args);
+ Diags.Report(IsCLMode() ? diag::warn_drv_unknown_argument_clang_cl :
+ diag::err_drv_unknown_argument)
+ << A->getAsString(Args);
return Args;
}
@@ -1710,8 +1712,11 @@ void Driver::BuildJobs(Compilation &C) const {
continue;
}
- Diag(clang::diag::warn_drv_unused_argument)
- << A->getAsString(C.getArgs());
+ // In clang-cl, don't mention unknown arguments here since they have
+ // already been warned about.
+ if (!IsCLMode() || !A->getOption().matches(options::OPT_UNKNOWN))
+ Diag(clang::diag::warn_drv_unused_argument)
+ << A->getAsString(C.getArgs());
}
}
}
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 2bbcb275a4b8..814eb353c5ce 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -9708,6 +9708,10 @@ std::unique_ptr<Command> visualstudio::Compiler::GetCommand(
options::OPT__SLASH_MT, options::OPT__SLASH_MTd))
A->render(Args, CmdArgs);
+ // Pass through all unknown arguments so that the fallback command can see
+ // them too.
+ Args.AddAllArgs(CmdArgs, options::OPT_UNKNOWN);
+
// Input filename.
assert(Inputs.size() == 1);
const InputInfo &II = Inputs[0];
diff --git a/clang/test/Driver/cl-fallback.c b/clang/test/Driver/cl-fallback.c
index e5ebde5c0182..f788e4cab162 100644
--- a/clang/test/Driver/cl-fallback.c
+++ b/clang/test/Driver/cl-fallback.c
@@ -3,6 +3,7 @@
// RUN: %clang_cl --target=i686-pc-win32 /fallback /Dfoo=bar /Ubaz /Ifoo /O0 /Ox /GR /GR- /Gy /Gy- \
// RUN: /Gw /Gw- /LD /LDd /EHs /EHs- /Zl /MD /MDd /MTd /MT /FImyheader.h /Zi \
+// RUN: -garbage -moregarbage \
// RUN: -### -- %s 2>&1 \
// RUN: | FileCheck %s
// CHECK: "-fdiagnostics-format" "msvc-fallback"
@@ -31,6 +32,8 @@
// CHECK: "/EHs-"
// CHECK: "/Zl"
// CHECK: "/MT"
+// CHECK: "-garbage"
+// CHECK: "-moregarbage"
// CHECK: "/Tc" "{{.*cl-fallback.c}}"
// CHECK: "/Fo{{.*cl-fallback.*.obj}}"
diff --git a/clang/test/Driver/unknown-arg.c b/clang/test/Driver/unknown-arg.c
index f834a0e8db92..09889bf1a879 100644
--- a/clang/test/Driver/unknown-arg.c
+++ b/clang/test/Driver/unknown-arg.c
@@ -1,5 +1,11 @@
// RUN: not %clang %s -cake-is-lie -%0 -%d -HHHH -munknown-to-clang-option -print-stats -funknown-to-clang-option 2>&1 | \
// RUN: FileCheck %s
+// RUN: %clang_cl -cake-is-lie -%0 -%d -HHHH -munknown-to-clang-option -print-stats -funknown-to-clang-option -c -- %s 2>&1 | \
+// RUN: FileCheck %s --check-prefix=CL
+// RUN: not %clang_cl -cake-is-lie -%0 -%d -HHHH -munknown-to-clang-option -print-stats -funknown-to-clang-option -c -Werror=unknown-argument -- %s 2>&1 | \
+// RUN: FileCheck %s --check-prefix=CL
+// RUN: %clang_cl -cake-is-lie -%0 -%d -HHHH -munknown-to-clang-option -print-stats -funknown-to-clang-option -c -Wno-unknown-argument -- %s 2>&1 | \
+// RUN: FileCheck %s --check-prefix=SILENT --allow-empty
// CHECK: unknown argument: '-cake-is-lie'
// CHECK: unknown argument: '-%0'
@@ -8,6 +14,15 @@
// CHECK: unknown argument: '-munknown-to-clang-option'
// CHECK: unknown argument: '-print-stats'
// CHECK: unknown argument: '-funknown-to-clang-option'
+// CL: unknown argument ignored in clang-cl: '-cake-is-lie'
+// CL: unknown argument ignored in clang-cl: '-%0'
+// CL: unknown argument ignored in clang-cl: '-%d'
+// CL: unknown argument ignored in clang-cl: '-HHHH'
+// CL: unknown argument ignored in clang-cl: '-munknown-to-clang-option'
+// CL: unknown argument ignored in clang-cl: '-print-stats'
+// CL: unknown argument ignored in clang-cl: '-funknown-to-clang-option'
+// SILENT-NOT: error
+// SILENT-NOT: warning
// RUN: %clang -S %s -o %t.s -Wunknown-to-clang-option 2>&1 | FileCheck --check-prefix=IGNORED %s
diff --git a/clang/test/Misc/serialized-diags-driver.c b/clang/test/Misc/serialized-diags-driver.c
index ad07d666c8c1..617ac8c6ef92 100644
--- a/clang/test/Misc/serialized-diags-driver.c
+++ b/clang/test/Misc/serialized-diags-driver.c
@@ -5,10 +5,10 @@
// doesn't litter the user's system with preprocessed output.
// RUN: rm -f %t
-// RUN: %clang -Wx-unknown-warning -Wall -fsyntax-only --serialize-diagnostics %t.diag %s
+// RUN: %clang -Wx-typoed-warning -Wall -fsyntax-only --serialize-diagnostics %t.diag %s
// RUN: c-index-test -read-diagnostics %t.diag 2>&1 | FileCheck %s
-// CHECK: warning: unknown warning option '-Wx-unknown-warning' [-Wunknown-warning-option] []
+// CHECK: warning: unknown warning option '-Wx-typoed-warning' [-Wunknown-warning-option] []
// CHECK: warning: variable 'voodoo' is uninitialized when used here [-Wuninitialized]
// CHECK: note: initialize the variable 'voodoo' to silence this warning []