[clang] [sanitizer] Fix empty string in unsupported argument error for -fsanitize-trap (PR #136549)

[Sinkevich Artem via cfe-commits]

https://github.com/ArtSin created https://github.com/llvm/llvm-project/pull/136549

When using `-fsanitize-trap` with a sanitizer group that doesn't support trapping, an empty argument is passed to `err_drv_unsupported_option_argument`. Expand groups for the diagnostic.

>From 459d375073093ebec33bcac0e824385daeadcf5f Mon Sep 17 00:00:00 2001
From: Artem Sinkevich <a.sinkevich at ispras.ru>
Date: Mon, 21 Apr 2025 12:48:51 +0400
Subject: [PATCH] [sanitizer] Fix empty string in unsupported argument error
 for -fsanitize-trap

When using `-fsanitize-trap` with a sanitizer group that doesn't support
trapping, an empty argument is passed to `err_drv_unsupported_option_argument`.
Expand groups for the diagnostic.
---
 clang/lib/Driver/SanitizerArgs.cpp | 4 ++--
 clang/test/Driver/fsanitize.c      | 3 +++
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
index f27cb813012f2..05ca2656c6522 100644
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -286,7 +286,7 @@ parseSanitizeArgs(const Driver &D, const llvm::opt::ArgList &Args,
               Add & AlwaysOut & ~DiagnosedAlwaysOutViolations) {
         if (DiagnoseErrors) {
           SanitizerSet SetToDiagnose;
-          SetToDiagnose.Mask |= KindsToDiagnose;
+          SetToDiagnose.Mask |= expandSanitizerGroups(KindsToDiagnose);
           D.Diag(diag::err_drv_unsupported_option_argument)
               << Arg->getSpelling() << toString(SetToDiagnose);
           DiagnosedAlwaysOutViolations |= KindsToDiagnose;
@@ -302,7 +302,7 @@ parseSanitizeArgs(const Driver &D, const llvm::opt::ArgList &Args,
               Remove & AlwaysIn & ~DiagnosedAlwaysInViolations) {
         if (DiagnoseErrors) {
           SanitizerSet SetToDiagnose;
-          SetToDiagnose.Mask |= KindsToDiagnose;
+          SetToDiagnose.Mask |= expandSanitizerGroups(KindsToDiagnose);
           D.Diag(diag::err_drv_unsupported_option_argument)
               << Arg->getSpelling() << toString(SetToDiagnose);
           DiagnosedAlwaysInViolations |= KindsToDiagnose;
diff --git a/clang/test/Driver/fsanitize.c b/clang/test/Driver/fsanitize.c
index c154e339941f2..434e6fd8c4a15 100644
--- a/clang/test/Driver/fsanitize.c
+++ b/clang/test/Driver/fsanitize.c
@@ -259,6 +259,9 @@
 // RUN: not %clang --target=aarch64-linux -fsanitize=memtag -I +mte %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-SANMT-NOMT-1
 // CHECK-SANMT-NOMT-1: '-fsanitize=memtag-stack' requires hardware support (+memtag)
 
+// RUN: not %clang --target=aarch64-linux-android31 -fsanitize-trap=memtag -march=armv8-a+memtag -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-SANMT-TRAP
+// CHECK-SANMT-TRAP: error: unsupported argument 'memtag-stack,memtag-heap,memtag-globals' to option '-fsanitize-trap='
+
 // RUN: %clang --target=x86_64-linux-gnu -fsanitize=address -fsanitize-address-use-after-scope %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-USE-AFTER-SCOPE
 // RUN: %clang_cl --target=x86_64-windows -fsanitize=address -fsanitize-address-use-after-scope -### -- %s 2>&1 | FileCheck %s --check-prefix=CHECK-USE-AFTER-SCOPE
 // CHECK-USE-AFTER-SCOPE: -cc1{{.*}}-fsanitize-address-use-after-scope