https://github.com/srividya-sundaram updated https://github.com/llvm/llvm-project/pull/200318
>From 928d8589b0b4188aaa9a8fb8bfb5aaa7a9194f5e Mon Sep 17 00:00:00 2001 From: srividya sundaram <[email protected]> Date: Tue, 26 May 2026 10:06:00 -0700 Subject: [PATCH 1/4] [Driver][SYCL] Verify that a .c file compiled with -fsycl is treated as C++ with a warning --- .../clang/Basic/DiagnosticDriverKinds.td | 5 ++++ clang/lib/Driver/Driver.cpp | 26 +++++++++++++++++-- clang/test/Driver/sycl-c-warn.c | 7 +++++ 3 files changed, 36 insertions(+), 2 deletions(-) create mode 100644 clang/test/Driver/sycl-c-warn.c diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td index 020014dabacfd..9a90b03c45b25 100644 --- a/clang/include/clang/Basic/DiagnosticDriverKinds.td +++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td @@ -533,6 +533,11 @@ def warn_drv_overriding_complex_range : Warning< def warn_drv_treating_input_as_cxx : Warning< "treating '%0' input as '%1' when in C++ mode, this behavior is deprecated">, InGroup<Deprecated>; +def warn_drv_fsycl_with_c_type : Warning< + "treating '%0' input as '%1' when -fsycl is used">, + InGroup<InvalidCommandLineArgument>; +def err_drv_fsycl_with_c_type : Error< + "'%0' must not be used in conjunction with '-fsycl', which expects C++ source">; def warn_drv_pch_not_first_include : Warning< "precompiled header '%0' was ignored because '%1' is not first '-include'">; def warn_drv_pch_ignoring_gch_file : Warning< diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp index ed3ddd130d6c7..bd30512ce9265 100644 --- a/clang/lib/Driver/Driver.cpp +++ b/clang/lib/Driver/Driver.cpp @@ -3070,12 +3070,13 @@ void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args, // actually use it, so we warn about unused -x arguments. types::ID InputType = types::TY_Nothing; Arg *InputTypeArg = nullptr; + bool IsSYCL = Args.hasFlag(options::OPT_fsycl, options::OPT_fno_sycl, false); // The last /TC or /TP option sets the input type to C or C++ globally. if (Arg *TCTP = Args.getLastArgNoClaim(options::OPT__SLASH_TC, options::OPT__SLASH_TP)) { InputTypeArg = TCTP; - InputType = TCTP->getOption().matches(options::OPT__SLASH_TC) + InputType = TCTP->getOption().matches(options::OPT__SLASH_TC) && !IsSYCL ? types::TY_C : types::TY_CXX; @@ -3142,6 +3143,21 @@ void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args, if (const char *Ext = strrchr(Value, '.')) Ty = TC.LookupTypeForExtension(Ext + 1); + // For SYCL, convert C-type sources to C++-type sources. + if (IsSYCL) { + types::ID OldTy = Ty; + switch (Ty) { + case types::TY_C: Ty = types::TY_CXX; break; + case types::TY_CHeader: Ty = types::TY_CXXHeader; break; + case types::TY_PP_C: Ty = types::TY_PP_CXX; break; + case types::TY_PP_CHeader: Ty = types::TY_PP_CXXHeader; break; + default: break; + } + if (OldTy != Ty) + Diag(clang::diag::warn_drv_fsycl_with_c_type) + << getTypeName(OldTy) << getTypeName(Ty); + } + if (Ty == types::TY_INVALID) { if (IsCLMode() && (Args.hasArgNoClaim(options::OPT_E) || CCGenDiagnostics)) Ty = types::TY_CXX; @@ -3219,7 +3235,8 @@ void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args, if (DiagnoseInputExistence(Value, types::TY_C, /*TypoCorrect=*/false)) { Arg *InputArg = makeInputArg(Args, Opts, A->getValue()); - Inputs.push_back(std::make_pair(types::TY_C, InputArg)); + Inputs.push_back( + std::make_pair(IsSYCL ? types::TY_CXX : types::TY_C, InputArg)); } A->claim(); } else if (A->getOption().matches(options::OPT__SLASH_Tp)) { @@ -3248,6 +3265,11 @@ void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args, InputType = types::TY_Object; } + // Emit an error if C compilation is forced in -fsycl mode. + if (IsSYCL && (InputType == types::TY_C || InputType == types::TY_PP_C || + InputType == types::TY_CHeader)) + Diag(clang::diag::err_drv_fsycl_with_c_type) << A->getAsString(Args); + // If the user has put -fmodule-header{,=} then we treat C++ headers as // header unit inputs. So we 'promote' -xc++-header appropriately. if (InputType == types::TY_CXXHeader && hasHeaderMode()) diff --git a/clang/test/Driver/sycl-c-warn.c b/clang/test/Driver/sycl-c-warn.c new file mode 100644 index 0000000000000..4f3474add0f1c --- /dev/null +++ b/clang/test/Driver/sycl-c-warn.c @@ -0,0 +1,7 @@ +// Verify that a .c file compiled with -fsycl is treated as C++ with a warning. +// RUN: %clang -### -fsycl %s 2>&1 | FileCheck -check-prefix WARN %s +// WARN: warning: treating 'c' input as 'c++' when -fsycl is used + +// Verify that explicitly forcing -x c with -fsycl is an error. +// RUN: %clang -### -fsycl -x c %s 2>&1 | FileCheck -check-prefix ERR %s +// ERR: error: '-x c' must not be used in conjunction with '-fsycl', which expects C++ source >From bb2c790e47038d113f01bf867a480b0d74ebe8e0 Mon Sep 17 00:00:00 2001 From: srividya sundaram <[email protected]> Date: Thu, 28 May 2026 20:01:57 -0700 Subject: [PATCH 2/4] Update test. --- clang/test/Driver/sycl-c-warn.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/clang/test/Driver/sycl-c-warn.c b/clang/test/Driver/sycl-c-warn.c index 4f3474add0f1c..df21103898639 100644 --- a/clang/test/Driver/sycl-c-warn.c +++ b/clang/test/Driver/sycl-c-warn.c @@ -1,7 +1,7 @@ // Verify that a .c file compiled with -fsycl is treated as C++ with a warning. // RUN: %clang -### -fsycl %s 2>&1 | FileCheck -check-prefix WARN %s -// WARN: warning: treating 'c' input as 'c++' when -fsycl is used +// WARN: warning: treating 'c' input as 'c++' when -fsycl is used [-Winvalid-command-line-argument] // Verify that explicitly forcing -x c with -fsycl is an error. -// RUN: %clang -### -fsycl -x c %s 2>&1 | FileCheck -check-prefix ERR %s +// RUN: not %clang -### -fsycl -x c %s 2>&1 | FileCheck -check-prefix ERR %s // ERR: error: '-x c' must not be used in conjunction with '-fsycl', which expects C++ source >From cc232aa8017621757ebabdf7dc1f1fb93b27ec19 Mon Sep 17 00:00:00 2001 From: srividya sundaram <[email protected]> Date: Thu, 28 May 2026 20:08:28 -0700 Subject: [PATCH 3/4] clang format --- clang/lib/Driver/Driver.cpp | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp index bd30512ce9265..1439ba718b718 100644 --- a/clang/lib/Driver/Driver.cpp +++ b/clang/lib/Driver/Driver.cpp @@ -3147,11 +3147,20 @@ void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args, if (IsSYCL) { types::ID OldTy = Ty; switch (Ty) { - case types::TY_C: Ty = types::TY_CXX; break; - case types::TY_CHeader: Ty = types::TY_CXXHeader; break; - case types::TY_PP_C: Ty = types::TY_PP_CXX; break; - case types::TY_PP_CHeader: Ty = types::TY_PP_CXXHeader; break; - default: break; + case types::TY_C: + Ty = types::TY_CXX; + break; + case types::TY_CHeader: + Ty = types::TY_CXXHeader; + break; + case types::TY_PP_C: + Ty = types::TY_PP_CXX; + break; + case types::TY_PP_CHeader: + Ty = types::TY_PP_CXXHeader; + break; + default: + break; } if (OldTy != Ty) Diag(clang::diag::warn_drv_fsycl_with_c_type) >From 59ffd02a26b9abfa05999e8cda57c9e4ea48f5d5 Mon Sep 17 00:00:00 2001 From: srividya sundaram <[email protected]> Date: Fri, 29 May 2026 08:38:55 -0700 Subject: [PATCH 4/4] [Driver][SYCL] Reuse existing C-to-C++ input promotion for -fsycl MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Instead of adding SYCL-specific diagnostics and a duplicate type-promotion switch, extend the existing CCCIsCXX() path in BuildInputs to also trigger when -fsycl is active. This reuses types::lookupCXXTypeForCType() for the C→C++ type promotion and warn_drv_treating_input_as_cxx for the warning. The -x c error case is similarly replaced with the generic err_drv_argument_not_allowed_with diagnostic. --- .../clang/Basic/DiagnosticDriverKinds.td | 5 ---- clang/lib/Driver/Driver.cpp | 30 +++---------------- clang/test/Driver/sycl-c-warn.c | 4 +-- 3 files changed, 6 insertions(+), 33 deletions(-) diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td index 9a90b03c45b25..020014dabacfd 100644 --- a/clang/include/clang/Basic/DiagnosticDriverKinds.td +++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td @@ -533,11 +533,6 @@ def warn_drv_overriding_complex_range : Warning< def warn_drv_treating_input_as_cxx : Warning< "treating '%0' input as '%1' when in C++ mode, this behavior is deprecated">, InGroup<Deprecated>; -def warn_drv_fsycl_with_c_type : Warning< - "treating '%0' input as '%1' when -fsycl is used">, - InGroup<InvalidCommandLineArgument>; -def err_drv_fsycl_with_c_type : Error< - "'%0' must not be used in conjunction with '-fsycl', which expects C++ source">; def warn_drv_pch_not_first_include : Warning< "precompiled header '%0' was ignored because '%1' is not first '-include'">; def warn_drv_pch_ignoring_gch_file : Warning< diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp index 1439ba718b718..4b62963270b96 100644 --- a/clang/lib/Driver/Driver.cpp +++ b/clang/lib/Driver/Driver.cpp @@ -3143,30 +3143,6 @@ void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args, if (const char *Ext = strrchr(Value, '.')) Ty = TC.LookupTypeForExtension(Ext + 1); - // For SYCL, convert C-type sources to C++-type sources. - if (IsSYCL) { - types::ID OldTy = Ty; - switch (Ty) { - case types::TY_C: - Ty = types::TY_CXX; - break; - case types::TY_CHeader: - Ty = types::TY_CXXHeader; - break; - case types::TY_PP_C: - Ty = types::TY_PP_CXX; - break; - case types::TY_PP_CHeader: - Ty = types::TY_PP_CXXHeader; - break; - default: - break; - } - if (OldTy != Ty) - Diag(clang::diag::warn_drv_fsycl_with_c_type) - << getTypeName(OldTy) << getTypeName(Ty); - } - if (Ty == types::TY_INVALID) { if (IsCLMode() && (Args.hasArgNoClaim(options::OPT_E) || CCGenDiagnostics)) Ty = types::TY_CXX; @@ -3180,7 +3156,8 @@ void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args, // If the driver is invoked as C++ compiler (like clang++ or c++) it // should autodetect some input files as C++ for g++ compatibility. - if (CCCIsCXX()) { + // -fsycl also requires C++ sources, so apply the same promotion. + if (CCCIsCXX() || IsSYCL) { types::ID OldTy = Ty; Ty = types::lookupCXXTypeForCType(Ty); @@ -3277,7 +3254,8 @@ void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args, // Emit an error if C compilation is forced in -fsycl mode. if (IsSYCL && (InputType == types::TY_C || InputType == types::TY_PP_C || InputType == types::TY_CHeader)) - Diag(clang::diag::err_drv_fsycl_with_c_type) << A->getAsString(Args); + Diag(clang::diag::err_drv_argument_not_allowed_with) + << A->getAsString(Args) << "-fsycl"; // If the user has put -fmodule-header{,=} then we treat C++ headers as // header unit inputs. So we 'promote' -xc++-header appropriately. diff --git a/clang/test/Driver/sycl-c-warn.c b/clang/test/Driver/sycl-c-warn.c index df21103898639..9de4067daaa53 100644 --- a/clang/test/Driver/sycl-c-warn.c +++ b/clang/test/Driver/sycl-c-warn.c @@ -1,7 +1,7 @@ // Verify that a .c file compiled with -fsycl is treated as C++ with a warning. // RUN: %clang -### -fsycl %s 2>&1 | FileCheck -check-prefix WARN %s -// WARN: warning: treating 'c' input as 'c++' when -fsycl is used [-Winvalid-command-line-argument] +// WARN: warning: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated [-Wdeprecated] // Verify that explicitly forcing -x c with -fsycl is an error. // RUN: not %clang -### -fsycl -x c %s 2>&1 | FileCheck -check-prefix ERR %s -// ERR: error: '-x c' must not be used in conjunction with '-fsycl', which expects C++ source +// ERR: error: invalid argument '-x c' not allowed with '-fsycl' _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
