From e875f458055d6a7b54d2d853590ccc2495ab145b Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@qt.io>
Date: Fri, 15 May 2020 12:47:09 +0200
Subject: [PATCH] CMake: Don't create *Depends header for header-only modules

Set the target property INTERFACE_MODULE_IS_HEADER_ONLY for
header-only modules, and only create *Depends header files if this
property is falsy.

Change-Id: Ic6b100787d18b3ff1f7b9d0f2b5c744018b1f295
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
---
 cmake/QtBuild.cmake       | 9 +++++++--
 cmake/QtPostProcess.cmake | 3 ++-
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
index f1634e54f68..a2fcdaed378 100644
--- a/cmake/QtBuild.cmake
+++ b/cmake/QtBuild.cmake
@@ -1923,6 +1923,7 @@ function(qt_add_module target)
     if(${arg_HEADER_MODULE})
         add_library("${target}" INTERFACE)
         set(is_interface_lib 1)
+        set_target_properties(${target} PROPERTIES INTERFACE_MODULE_IS_HEADER_ONLY TRUE)
     elseif(${arg_STATIC})
         add_library("${target}" STATIC)
     elseif(${QT_BUILD_SHARED_LIBS})
@@ -2037,7 +2038,11 @@ function(qt_add_module target)
         ### FIXME: Can we replace headers.pri?
         set(module_include_dir "${QT_BUILD_DIR}/${INSTALL_INCLUDEDIR}/${module_include_name}")
         qt_read_headers_pri("${module_include_dir}" "module_headers")
-        set(module_depends_header "${module_include_dir}/${module}Depends")
+        if(arg_HEADER_MODULE)
+            set(module_depends_header "")
+        else()
+            set(module_depends_header "${module_include_dir}/${module}Depends")
+        endif()
         if(is_framework)
             if(NOT is_interface_lib)
                 set(public_headers_to_copy "${module_headers_public}" "${module_depends_header}")
@@ -2046,7 +2051,7 @@ function(qt_add_module target)
             endif()
         else()
             set_property(TARGET ${target} APPEND PROPERTY PUBLIC_HEADER "${module_headers_public}")
-            set_property(TARGET ${target} APPEND PROPERTY PUBLIC_HEADER ${module_depends_header})
+            set_property(TARGET ${target} APPEND PROPERTY PUBLIC_HEADER "${module_depends_header}")
             set_property(TARGET ${target} APPEND PROPERTY PRIVATE_HEADER "${module_headers_private}")
         endif()
         if (NOT ${arg_HEADER_MODULE})
diff --git a/cmake/QtPostProcess.cmake b/cmake/QtPostProcess.cmake
index 8fbdf103c32..a99661f6928 100644
--- a/cmake/QtPostProcess.cmake
+++ b/cmake/QtPostProcess.cmake
@@ -169,7 +169,8 @@ function(qt_internal_create_module_depends_file target)
     endif()
 
     get_target_property(hasModuleHeaders "${target}" INTERFACE_MODULE_HAS_HEADERS)
-    if (${hasModuleHeaders})
+    get_target_property(isHeaderModule "${target}" INTERFACE_MODULE_IS_HEADER_ONLY)
+    if (hasModuleHeaders AND NOT isHeaderModule)
         get_target_property(module_include_name "${target}" INTERFACE_MODULE_INCLUDE_NAME)
         qt_internal_write_depends_file(${module_include_name} ${qtdeps})
     endif()