From 966c39802ee65ac0732d23c92535fbaaddd8a58e Mon Sep 17 00:00:00 2001
From: Maarten Bent <MaartenBent@users.noreply.github.com>
Date: Sun, 28 Jan 2024 14:04:29 +0100
Subject: [PATCH] CMake: Throw a more descriptive error when submodule files do
 not exist

Instead of having a long list of files that cannot be found, create an
error message that mentions that the git submodule should be checked out.
---
 build/cmake/functions.cmake | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/build/cmake/functions.cmake b/build/cmake/functions.cmake
index d85541509e..50da094963 100644
--- a/build/cmake/functions.cmake
+++ b/build/cmake/functions.cmake
@@ -593,6 +593,12 @@ endfunction()
 function(wx_add_builtin_library name)
     wx_list_add_prefix(src_list "${wxSOURCE_DIR}/" ${ARGN})
 
+    list(GET src_list 0 src_file)
+    if(NOT EXISTS "${src_file}")
+        message(FATAL_ERROR "${name} file does not exist: \"${src_file}\".\
+        Make sure you checkout the git submodules.")
+    endif()
+
     if(${name} MATCHES "wx.*")
         string(SUBSTRING ${name} 2 -1 name_short)
     else()