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

[Sinkevich Artem via cfe-commits]

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

>From 626d7e1fa3ce19c0bed7273f07439ff85f3de58c 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`.
Use new `toStringWithGroups` for the diagnostic.
---
 clang/lib/Driver/SanitizerArgs.cpp | 21 +++++++++++++++++++--
 clang/test/Driver/fsanitize.c      |  3 +++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
index 85c4a754f93c5..eb4718909c951 100644
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -160,6 +160,10 @@ static std::string describeSanitizeArg(const llvm::opt::Arg *A,
 /// Sanitizers set.
 static std::string toString(const clang::SanitizerSet &Sanitizers);
 
+/// Produce a string containing comma-separated names of sanitizers and
+/// sanitizer groups in \p Sanitizers set.
+static std::string toStringWithGroups(const clang::SanitizerSet &Sanitizers);
+
 /// Return true if an execute-only target disallows data access to code
 /// sections.
 static bool isExecuteOnlyTarget(const llvm::Triple &Triple,
@@ -289,7 +293,7 @@ parseSanitizeArgs(const Driver &D, const llvm::opt::ArgList &Args,
           SanitizerSet SetToDiagnose;
           SetToDiagnose.Mask |= KindsToDiagnose;
           D.Diag(diag::err_drv_unsupported_option_argument)
-              << Arg->getSpelling() << toString(SetToDiagnose);
+              << Arg->getSpelling() << toStringWithGroups(SetToDiagnose);
           DiagnosedAlwaysOutViolations |= KindsToDiagnose;
         }
       }
@@ -305,7 +309,7 @@ parseSanitizeArgs(const Driver &D, const llvm::opt::ArgList &Args,
           SanitizerSet SetToDiagnose;
           SetToDiagnose.Mask |= KindsToDiagnose;
           D.Diag(diag::err_drv_unsupported_option_argument)
-              << Arg->getSpelling() << toString(SetToDiagnose);
+              << Arg->getSpelling() << toStringWithGroups(SetToDiagnose);
           DiagnosedAlwaysInViolations |= KindsToDiagnose;
         }
       }
@@ -1200,6 +1204,19 @@ static std::string toString(const clang::SanitizerMaskCutoffs &Cutoffs) {
   return llvm::join(Res, ",");
 }
 
+static std::string toStringWithGroups(const clang::SanitizerSet &Sanitizers) {
+  std::string Res;
+#define SANITIZER(NAME, ID)                                                    \
+  if (Sanitizers.has(SanitizerKind::ID)) {                                     \
+    if (!Res.empty())                                                          \
+      Res += ",";                                                              \
+    Res += NAME;                                                               \
+  }
+#define SANITIZER_GROUP(NAME, ID, ALIAS) SANITIZER(NAME, ID##Group)
+#include "clang/Basic/Sanitizers.def"
+  return Res;
+}
+
 static void addSpecialCaseListOpt(const llvm::opt::ArgList &Args,
                                   llvm::opt::ArgStringList &CmdArgs,
                                   const char *SCLOptFlag,
diff --git a/clang/test/Driver/fsanitize.c b/clang/test/Driver/fsanitize.c
index 24d64c94c0956..1f696aba8d088 100644
--- a/clang/test/Driver/fsanitize.c
+++ b/clang/test/Driver/fsanitize.c
@@ -317,6 +317,9 @@
 // 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' 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