Wrap the GNU/Clang compiler-dependent flags with genex conditions

If flags use CMake scopes that propagate them to user libraries, it may
lead to an issue, if user projects are built using different compiler.
We need to guard these flags to make sure that they only will apply to
respective compilers.

Change-Id: I0fd5847447bd8373e8e07f64dae11f27f48c915d
Reviewed-by: Alexandru Croitor (OOO) <[email protected]>
Reviewed-by: Amir Masoud Abdol <[email protected]>
(cherry picked from commit a2b6c2f3437bf1779da787e719bea08bc6f28622)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>

1 files changed, 21 insertions, 3 deletions

diff --git a/cmake/QtFlagHandlingHelpers.cmake b/cmake/QtFlagHandlingHelpers.cmake
index 7cc072edb73..3ce54181469 100644
--- a/cmake/QtFlagHandlingHelpers.cmake
+++ b/cmake/QtFlagHandlingHelpers.cmake
@@ -128,6 +128,16 @@ function(qt_internal_apply_gc_binaries target visibility)
         message(FATAL_ERROR "Visibitily setting must be one of PRIVATE, INTERFACE or PUBLIC.")
     endif()
 
+    string(JOIN "" clang_or_gcc_begin
+        "$<$<OR:"
+            "$<CXX_COMPILER_ID:GNU>,"
+            "$<CXX_COMPILER_ID:Clang>,"
+            "$<CXX_COMPILER_ID:AppleClang>,"
+            "$<CXX_COMPILER_ID:IntelLLVM>"
+        ">:"
+    )
+    set(clang_or_gcc_end ">")
+
     if ((GCC OR CLANG) AND NOT WASM AND NOT UIKIT AND NOT MSVC)
         if(APPLE)
             set(gc_sections_flag "-Wl,-dead_strip")
@@ -136,16 +146,19 @@ function(qt_internal_apply_gc_binaries target visibility)
         elseif(LINUX OR BSD OR WIN32 OR ANDROID)
             set(gc_sections_flag "-Wl,--gc-sections")
         endif()
+        set(gc_sections_flag
+            "${clang_or_gcc_begin}${gc_sections_flag}${clang_or_gcc_end}")
     endif()
     if(gc_sections_flag)
         target_link_options("${target}" ${visibility} "${gc_sections_flag}")
     endif()
 
     if((GCC OR CLANG) AND NOT WASM AND NOT UIKIT AND NOT MSVC)
-        set(split_sections_flags "-ffunction-sections" "-fdata-sections")
+        set(split_sections_flags
+            "${clang_or_gcc_begin}-ffunction-sections;-fdata-sections${clang_or_gcc_end}")
     endif()
     if(split_sections_flags)
-        target_compile_options("${target}" ${visibility} ${split_sections_flags})
+        target_compile_options("${target}" ${visibility} "${split_sections_flags}")
     endif()
 endfunction()
 
@@ -160,7 +173,12 @@ function(qt_internal_apply_intel_cet target visibility)
     endif()
 
     if(GCC)
-        set(flags "-mshstk")
+        string(JOIN "" flags
+            "$<$<OR:"
+                "$<CXX_COMPILER_ID:GNU>,"
+                "$<CXX_COMPILER_ID:Clang>,"
+                "$<CXX_COMPILER_ID:AppleClang>"
+            ">:-mshstk>")
     endif()
     if(flags)
         target_compile_options("${target}" ${visibility} "${flags}")