From 99b76c91a0e7e53b645a1db92b9cb1dd573a3e26 Mon Sep 17 00:00:00 2001
From: NLeeson <94591016+NLeeson@users.noreply.github.com>
Date: Thu, 24 Sep 2026 03:11:54 +0200
Subject: [PATCH] build: handle IntelLLVM as Clang for warnings and mitigations

IntelLLVM falls through to GCC-only flags, breaking the build and selecting
unsupported Spectre mitigations.

Signed-off-by: NLeeson <94591016+NLeeson@users.noreply.github.com>
---
 CMakeLists.txt | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0ae60308614f1..524c2daef9bae 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -796,14 +796,14 @@ if(NOT NEO_DISABLE_MITIGATIONS)
       message(WARNING "Spectre mitigation is not supported by the compiler")
     endif()
   else()
-    if(${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang")
+    if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM")
       check_cxx_compiler_flag(-mretpoline COMPILER_SUPPORTS_RETPOLINE)
       if(COMPILER_SUPPORTS_RETPOLINE)
         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mretpoline")
       else()
         message(WARNING "Spectre mitigation -mretpoline flag is not supported by the compiler")
       endif()
-    else()
+    elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
       check_cxx_compiler_flag(-mindirect-branch=thunk COMPILER_SUPPORTS_INDIRECT_BRANCH_THUNK)
       if(COMPILER_SUPPORTS_INDIRECT_BRANCH_THUNK)
         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mindirect-branch=thunk")
@@ -867,13 +867,13 @@ if(NOT MSVC)
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unused-parameter") # needed for unused function arguments
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-missing-field-initializers") # needed for dependencies, e.g. gmmlib
 
-  if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
-    # clang only
+  if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM")
+    # Clang and IntelLLVM diagnostics
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wshorten-64-to-32 -Wno-extern-c-compat -Wno-instantiation-after-specialization")
-    if(WIN32 AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 19)
+    if(WIN32 AND CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 19)
       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-cast-function-type-mismatch")
     endif()
-  else()
+  elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
     # gcc only
     if(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 12)
       # Disable specific warnings due to GCC bug for versions >= 12