Fix searching for lld in $PATH on Linux

cmake/targets/BuildBun.cmake

@@ -820,8 +820,32 @@ elseif(APPLE)
     -fno-keep-static-consts
   )
 else()
+  # Try to use lld-16 if available, otherwise fallback to lld
+  # Cache it so we don't have to re-run CMake to pick it up
+  if(NOT DEFINED LLD_NAME)
+    find_program(LLD_EXECUTABLE_NAME lld-${LLVM_VERSION_MAJOR})
+
+    if(NOT LLD_EXECUTABLE_NAME)
+      if(CI)
+        # Ensure we don't use a differing version of lld in CI vs clang
+        message(FATAL_ERROR "lld-${LLVM_VERSION_MAJOR} not found. Please make sure you have LLVM ${LLVM_VERSION_MAJOR}.x installed and set to lld-${LLVM_VERSION_MAJOR}")
+      endif()
+
+      # To make it easier for contributors, allow differing versions of lld vs clang/cmake
+      find_program(LLD_EXECUTABLE_NAME lld)
+    endif()
+
+    if(NOT LLD_EXECUTABLE_NAME)
+      message(FATAL_ERROR "LLD not found. Please make sure you have LLVM ${LLVM_VERSION_MAJOR}.x installed and lld is available in your PATH as lld-${LLVM_VERSION_MAJOR}")
+    endif()
+
+    # normalize to basename so it can be used with -fuse-ld
+    get_filename_component(LLD_NAME ${LLD_EXECUTABLE_NAME} NAME CACHE)
+    message(STATUS "Using linker: ${LLD_NAME} (${LLD_EXECUTABLE_NAME})")
+  endif()
+
   target_link_options(${bun} PUBLIC
-    -fuse-ld=lld-${LLVM_VERSION_MAJOR}
+    -fuse-ld=${LLD_NAME}
     -fno-pic
     -static-libstdc++
     -static-libgcc