Cleanup: use string APPEND/PREPEND

Replace 'set' with 'string(APPEND/PREPEND ...)'.
This avoids duplicating the variable name.

4 files changed, 16 insertions, 16 deletions

diff --git a/extern/bullet2/CMakeLists.txt b/extern/bullet2/CMakeLists.txt
index 2c63d76296c..6138795f241 100644
--- a/extern/bullet2/CMakeLists.txt
+++ b/extern/bullet2/CMakeLists.txt
@@ -423,7 +423,7 @@ set(LIB
 
 if(CMAKE_COMPILER_IS_GNUCXX)
   # needed for gcc 4.6+
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fpermissive")
+  string(APPEND CMAKE_CXX_FLAGS " -fpermissive")
 endif()
 
 if(MSVC)
diff --git a/extern/draco/dracoenc/cmake/compiler_flags.cmake b/extern/draco/dracoenc/cmake/compiler_flags.cmake
index d842a8ab1f4..bbfb069d2d3 100644
--- a/extern/draco/dracoenc/cmake/compiler_flags.cmake
+++ b/extern/draco/dracoenc/cmake/compiler_flags.cmake
@@ -23,9 +23,9 @@ macro (add_c_flag_if_supported c_flag)
     message("Checking C compiler flag support for: " ${c_flag})
     check_c_compiler_flag("${c_flag}" C_FLAG_SUPPORTED)
     if (${C_FLAG_SUPPORTED})
-      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${c_flag}" CACHE STRING "")
+      string(APPEND CMAKE_C_FLAGS " ${c_flag}" CACHE STRING "")
     else ()
-      set(DRACO_FAILED_C_FLAGS "${DRACO_FAILED_C_FLAGS} ${c_flag}" CACHE STRING
+      string(APPEND DRACO_FAILED_C_FLAGS " ${c_flag}" CACHE STRING
           "" FORCE)
     endif ()
   endif ()
@@ -45,9 +45,9 @@ macro (add_cxx_flag_if_supported cxx_flag)
     message("Checking CXX compiler flag support for: " ${cxx_flag})
     check_cxx_compiler_flag("${cxx_flag}" CXX_FLAG_SUPPORTED)
     if (${CXX_FLAG_SUPPORTED})
-      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${cxx_flag}" CACHE STRING "")
+      string(APPEND CMAKE_CXX_FLAGS " ${cxx_flag}" CACHE STRING "")
     else()
-      set(DRACO_FAILED_CXX_FLAGS "${DRACO_FAILED_CXX_FLAGS} ${cxx_flag}" CACHE
+      string(APPEND DRACO_FAILED_CXX_FLAGS " ${cxx_flag}" CACHE
           STRING "" FORCE)
     endif ()
   endif ()
@@ -138,7 +138,7 @@ macro (append_as_flag flag)
   string(FIND "${DRACO_AS_FLAGS}" "${flag}" AS_FLAG_FOUND)
 
   if (${AS_FLAG_FOUND} EQUAL -1)
-    set(DRACO_AS_FLAGS "${DRACO_AS_FLAGS} ${flag}")
+    string(APPEND DRACO_AS_FLAGS " ${flag}")
   endif ()
 endmacro ()
 
@@ -148,7 +148,7 @@ macro (append_c_flag flag)
   string(FIND "${CMAKE_C_FLAGS}" "${flag}" C_FLAG_FOUND)
 
   if (${C_FLAG_FOUND} EQUAL -1)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}")
+    string(APPEND CMAKE_C_FLAGS " ${flag}")
   endif ()
 endmacro ()
 
@@ -158,7 +158,7 @@ macro (append_cxx_flag flag)
   string(FIND "${CMAKE_CXX_FLAGS}" "${flag}" CXX_FLAG_FOUND)
 
   if (${CXX_FLAG_FOUND} EQUAL -1)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}")
+    string(APPEND CMAKE_CXX_FLAGS " ${flag}")
   endif ()
 endmacro ()
 
@@ -174,7 +174,7 @@ macro (append_exe_linker_flag flag)
   string(FIND "${CMAKE_EXE_LINKER_FLAGS}" "${flag}" LINKER_FLAG_FOUND)
 
   if (${LINKER_FLAG_FOUND} EQUAL -1)
-    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${flag}")
+    string(APPEND CMAKE_EXE_LINKER_FLAGS " ${flag}")
   endif ()
 endmacro ()
 
@@ -191,7 +191,7 @@ function (append_link_flag_to_target target flags)
       return()
     endif ()
 
-    set(target_link_flags "${target_link_flags} ${flags}")
+    string(APPEND target_link_flags " ${flags}")
   else ()
     set(target_link_flags "${flags}")
   endif ()
diff --git a/extern/draco/dracoenc/cmake/compiler_tests.cmake b/extern/draco/dracoenc/cmake/compiler_tests.cmake
index e529ba11253..7cc3fbfc67d 100644
--- a/extern/draco/dracoenc/cmake/compiler_tests.cmake
+++ b/extern/draco/dracoenc/cmake/compiler_tests.cmake
@@ -41,9 +41,9 @@ macro(draco_check_c_compiles test_name test_source result_var)
     set(${result_var} ${C_TEST_COMPILED})
 
     if (${C_TEST_COMPILED})
-      set(DRACO_C_PASSED_TESTS "${DRACO_C_PASSED_TESTS} ${test_name}")
+      string(APPEND DRACO_C_PASSED_TESTS " ${test_name}")
     else ()
-      set(DRACO_C_FAILED_TESTS "${DRACO_C_FAILED_TESTS} ${test_name}")
+      string(APPEND DRACO_C_FAILED_TESTS " ${test_name}")
       message("C Compiler test ${test_name} failed.")
     endif ()
   elseif (NOT ${C_TEST_PASSED} EQUAL -1)
@@ -71,9 +71,9 @@ macro(draco_check_cxx_compiles test_name test_source result_var)
     set(${result_var} ${CXX_TEST_COMPILED})
 
     if (${CXX_TEST_COMPILED})
-      set(DRACO_CXX_PASSED_TESTS "${DRACO_CXX_PASSED_TESTS} ${test_name}")
+      string(APPEND DRACO_CXX_PASSED_TESTS " ${test_name}")
     else ()
-      set(DRACO_CXX_FAILED_TESTS "${DRACO_CXX_FAILED_TESTS} ${test_name}")
+      string(APPEND DRACO_CXX_FAILED_TESTS " ${test_name}")
       message("CXX Compiler test ${test_name} failed.")
     endif ()
   elseif (NOT ${CXX_TEST_PASSED} EQUAL -1)
diff --git a/extern/mantaflow/CMakeLists.txt b/extern/mantaflow/CMakeLists.txt
index fe6c72660e0..ee155ee8636 100644
--- a/extern/mantaflow/CMakeLists.txt
+++ b/extern/mantaflow/CMakeLists.txt
@@ -37,8 +37,8 @@ endif()
 
 if(APPLE AND ("${CMAKE_OSX_ARCHITECTURES}" STREQUAL "arm64"))
   if(CMAKE_COMPILER_IS_GNUCXX OR "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fvisibility=hidden")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fvisibility=hidden")
+    string(APPEND CMAKE_C_FLAGS " -fvisibility=hidden")
+    string(APPEND CMAKE_CXX_FLAGS " -fvisibility=hidden")
   endif()
 endif()