Remove HIP/ROCM includes ("-isystem /usr/include"), as they break inclusion of <math.h>.
Add inclusion of Clang resource dir (e.g. /usr/lib/clang/20), as it is used in hip runtime like that.
--- a/src/comgr-compiler.cpp
+++ b/src/comgr-compiler.cpp
@@ -1015,9 +1015,8 @@ AMDGPUCompiler::addTargetIdentifierFlags(llvm::StringRef IdentStr,
 }
 
 amd_comgr_status_t AMDGPUCompiler::addCompilationFlags() {
-  HIPIncludePath = (Twine(env::getHIPPath()) + "/include").str();
-  // HIP headers depend on hsa.h which is in ROCM_DIR/include.
-  ROCMIncludePath = (Twine(env::getROCMPath()) + "/include").str();
+  // Allow to include <include/cuda_wrappers/algorithm> (used in some hip files)
+  ClangIncludePath = @CLANG_RESOURCE_DIR@;
 
   // Default to O3 for all contexts
   Args.push_back("-O3");
@@ -1043,9 +1042,7 @@ amd_comgr_status_t AMDGPUCompiler::addCompilationFlags() {
     Args.push_back("-nogpuinc");
     Args.push_back("--offload-device-only");
     Args.push_back("-isystem");
-    Args.push_back(ROCMIncludePath.c_str());
-    Args.push_back("-isystem");
-    Args.push_back(HIPIncludePath.c_str());
+    Args.push_back(ClangIncludePath.c_str());
     // Pass a cuid that depends on the input files
     // Otherwise, a random (which depends on the /tmp/comgr-xxxxx path) cuid is
     // generated which causes a cache miss on every run.
--- a/src/comgr-compiler.h
+++ b/src/comgr-compiler.h
@@ -52,12 +52,7 @@ class AMDGPUCompiler {
   DataAction *ActionInfo;
   DataSet *InSet;
   amd_comgr_data_set_t OutSetT;
-  /// ROCM include Path
-  std::string ROCMIncludePath;
-  /// HIP and Clang Include Paths
-  std::string HIPIncludePath;
   std::string ClangIncludePath;
-  std::string ClangIncludePath2;
   /// Precompiled header file paths.
   llvm::SmallVector<llvm::SmallString<128>, 2> PrecompiledHeaders;
   /// Arguments common to all driver invocations in the current action.