[clang] [Clang] diagnosing missing Vulkan environment when using SPIR-V triple (PR #190840)

[via cfe-commits]

https://github.com/PrabbyDD updated https://github.com/llvm/llvm-project/pull/190840

>From 18508d94e3cde9cf47fa11fcc28803cc7966c5e4 Mon Sep 17 00:00:00 2001
From: PrabbyDD <dhaliprabh at gmail.com>
Date: Mon, 6 Apr 2026 15:43:31 -0700
Subject: [PATCH 1/4] first PR attempt on SPIRV diagnositic

---
 clang/include/clang/Basic/DiagnosticFrontendKinds.td |  3 +++
 clang/lib/Frontend/CompilerInstance.cpp              | 11 +++++++++++
 2 files changed, 14 insertions(+)

diff --git a/clang/include/clang/Basic/DiagnosticFrontendKinds.td b/clang/include/clang/Basic/DiagnosticFrontendKinds.td
index 62b74574102e4..7fa858c0d50be 100644
--- a/clang/include/clang/Basic/DiagnosticFrontendKinds.td
+++ b/clang/include/clang/Basic/DiagnosticFrontendKinds.td
@@ -43,6 +43,9 @@ def note_fe_backend_resource_limit: Note<"%0 (%1) exceeds limit (%2) in '%3'">,
 def remark_fe_backend_plugin: Remark<"%0">, BackendInfo, InGroup<RemarkBackendPlugin>;
 def note_fe_backend_plugin: Note<"%0">, BackendInfo;
 
+def err_spirv_requires_vulkan : Error
+    "SPIR-V target requires a Vulkan environment, e.g. '-target spirv64-unknown-vulkan1.3'">;
+
 def warn_fe_override_module : Warning<
     "overriding the module target triple with %0">,
     InGroup<DiagGroup<"override-module">>;
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index 0b00ad7128c00..89898d3adfbae 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -112,6 +112,17 @@ void CompilerInstance::setTarget(TargetInfo *Value) { Target = Value; }
 void CompilerInstance::setAuxTarget(TargetInfo *Value) { AuxTarget = Value; }
 
 bool CompilerInstance::createTarget() {
+
+  // Validate Vulkan environment for SPIRV. 
+  llvm::Triple Triple(getInvocation().getTargetOpts().Triple);
+  if (Triple.getArch() == llvm::Triple::spirv) {
+    if (Triple.getOS() != llvm::Triple::Vulkan ||
+        Triple.getVulkanVersion() == llvm::VersionTuple(0)) {
+      getDiagnostics().Report(diag::err_spirv_requires_vulkan) << Triple.str();
+      return false;
+    }
+  }
+
   // Create the target instance.
   setTarget(TargetInfo::CreateTargetInfo(getDiagnostics(),
                                          getInvocation().getTargetOpts()));

>From 2b0276129061915fc82c1639439c7b733215e196 Mon Sep 17 00:00:00 2001
From: PrabbyDD <dhaliprabh at gmail.com>
Date: Tue, 7 Apr 2026 13:04:38 -0700
Subject: [PATCH 2/4] [clang] generate diagnostic error instead of assert for
 invalid SPIR-V target for release

When a user passes '-target spirv' without specififying a vulkan environment ttriple, SPIRVTargetInfo will fire an assert instead of throwing an error diagnostic. Added this diagnostic in CompilerInstance::createTarget() before target is initialized. Fixes #189964
---
 clang/include/clang/Basic/DiagnosticFrontendKinds.td | 4 ++--
 clang/test/Driver/spirv-target-validation.c          | 4 ++++
 2 files changed, 6 insertions(+), 2 deletions(-)
 create mode 100644 clang/test/Driver/spirv-target-validation.c

diff --git a/clang/include/clang/Basic/DiagnosticFrontendKinds.td b/clang/include/clang/Basic/DiagnosticFrontendKinds.td
index 7fa858c0d50be..0a3e4e82a79e5 100644
--- a/clang/include/clang/Basic/DiagnosticFrontendKinds.td
+++ b/clang/include/clang/Basic/DiagnosticFrontendKinds.td
@@ -43,8 +43,8 @@ def note_fe_backend_resource_limit: Note<"%0 (%1) exceeds limit (%2) in '%3'">,
 def remark_fe_backend_plugin: Remark<"%0">, BackendInfo, InGroup<RemarkBackendPlugin>;
 def note_fe_backend_plugin: Note<"%0">, BackendInfo;
 
-def err_spirv_requires_vulkan : Error
-    "SPIR-V target requires a Vulkan environment, e.g. '-target spirv64-unknown-vulkan1.3'">;
+def err_spirv_requires_vulkan : Error<
+    "SPIR-V target requires a Vulkan environment (e.g. '-target spirv64-unknown-vulkan1.3')">;
 
 def warn_fe_override_module : Warning<
     "overriding the module target triple with %0">,
diff --git a/clang/test/Driver/spirv-target-validation.c b/clang/test/Driver/spirv-target-validation.c
new file mode 100644
index 0000000000000..cde5b46c54b94
--- /dev/null
+++ b/clang/test/Driver/spirv-target-validation.c
@@ -0,0 +1,4 @@
+// RUN: %clang -target spirv %s 2>&1 | FileCheck %s
+// CHECK: error: SPIR-V target requires a Vulkan environment
+
+int main() { return 0; }
\ No newline at end of file

>From 4c9d66e02d93864b6df3f4763f4ee5f354ec2c55 Mon Sep 17 00:00:00 2001
From: PrabbyDD <dhaliprabh at gmail.com>
Date: Tue, 7 Apr 2026 18:07:45 -0700
Subject: [PATCH 3/4] Fix formatting

---
 clang/lib/Frontend/CompilerInstance.cpp     | 3 ++-
 clang/test/Driver/spirv-target-validation.c | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index 89898d3adfbae..bca4532cf2fa8 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -113,7 +113,8 @@ void CompilerInstance::setAuxTarget(TargetInfo *Value) { AuxTarget = Value; }
 
 bool CompilerInstance::createTarget() {
 
-  // Validate Vulkan environment for SPIRV. 
+  // SPIR-V targeting requires a fully specified Vulkan environment.
+  // Validate here before CreateTargetInfo() to emit a proper diagnostic
   llvm::Triple Triple(getInvocation().getTargetOpts().Triple);
   if (Triple.getArch() == llvm::Triple::spirv) {
     if (Triple.getOS() != llvm::Triple::Vulkan ||
diff --git a/clang/test/Driver/spirv-target-validation.c b/clang/test/Driver/spirv-target-validation.c
index cde5b46c54b94..c87e528c75350 100644
--- a/clang/test/Driver/spirv-target-validation.c
+++ b/clang/test/Driver/spirv-target-validation.c
@@ -1,4 +1,4 @@
-// RUN: %clang -target spirv %s 2>&1 | FileCheck %s
+// RUN: not %clang -target spirv %s 2>&1 | FileCheck %s
 // CHECK: error: SPIR-V target requires a Vulkan environment
 
 int main() { return 0; }
\ No newline at end of file

>From 2f67bdb5a42d39eb6b29cad31c6dab09660bca14 Mon Sep 17 00:00:00 2001
From: PrabbyDD <dhaliprabh at gmail.com>
Date: Mon, 13 Apr 2026 07:40:35 -0700
Subject: [PATCH 4/4] added release note

---
 clang/docs/ReleaseNotes.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 1601be699a604..b00d0375f6fd1 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -374,7 +374,7 @@ Bug Fixes in This Version
 -------------------------
 
 - Fixed atomic boolean compound assignment; the conversion back to atomic bool would be miscompiled. (#GH33210)
-
+- Fixed an issue where an assert was thrown instead of an error if no vulkan env was specified with -target spirv (#GH#189964) 
 - Fixed a failed assertion in the preprocessor when ``__has_embed`` parameters are missing parentheses. (#GH175088)
 - Fix lifetime extension of temporaries in for-range-initializers in templates. (#GH165182)
 - Fixed a preprocessor crash in ``__has_cpp_attribute`` on incomplete scoped attributes. (#GH178098)