Add new target-property `IMPORTED_GLOBAL`.

The purpose of this new `IMPORTED_GLOBAL` target-property is to prolong
the lifetime and scope of `IMPORTED` targets in such a way as if they
had been created with the keyword `GLOBAL` in the first place.

* It can only be set to `TRUE`. That means, a local `IMPORTED` target
  can be promoted to global scope but a global `IMPORTED` target cannot
  be degraded to local scope!
* Setting it to `TRUE` only succeeds if done from within the same
  directory in which the `IMPORTED` target was created in the first
  place.

Fixes #17256.

1 files changed, 61 insertions, 0 deletions

diff --git a/Tests/RunCMake/set_property/IMPORTED_GLOBAL-stderr.txt b/Tests/RunCMake/set_property/IMPORTED_GLOBAL-stderr.txt
new file mode 100644
index 0000000..f21b1de
--- /dev/null
+++ b/Tests/RunCMake/set_property/IMPORTED_GLOBAL-stderr.txt
@@ -0,0 +1,61 @@
+^CMake Error at IMPORTED_GLOBAL.cmake:9 \(set_property\):
+  IMPORTED_GLOBAL property can't be set to FALSE on targets
+  \(\"ImportedGlobalTarget\"\)
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
+
+
+CMake Error at IMPORTED_GLOBAL.cmake:16 \(set_property\):
+  IMPORTED_GLOBAL property can't be appended, only set on imported targets
+  \(\"ImportedGlobalTarget\"\)
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
+
+
+CMake Error at IMPORTED_GLOBAL.cmake:26 \(set_property\):
+  IMPORTED_GLOBAL property can't be set to FALSE on targets
+  \(\"ImportedLocalTarget\"\)
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
+
+
+CMake Error at IMPORTED_GLOBAL.cmake:32 \(set_property\):
+  IMPORTED_GLOBAL property can't be set on non-imported targets
+  \(\"NonImportedTarget\"\)
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
+
+
+CMake Error at IMPORTED_GLOBAL/CMakeLists.txt:8 \(set_property\):
+  Attempt to promote imported target \"ImportedLocalTarget2\" to global scope
+  \(by setting IMPORTED_GLOBAL\) which is not built in this directory.
+
+
+CMake Error in IMPORTED_GLOBAL/CMakeLists.txt:
+  IMPORTED_GLOBAL property can't be set to FALSE on targets
+  \(\"ImportedSubdirTarget1\"\)
+
+
+
+CMake Error at IMPORTED_GLOBAL.cmake:50 \(set_property\):
+  Attempt to promote imported target \"ImportedSubdirTarget1\" to global scope
+  \(by setting IMPORTED_GLOBAL\) which is not built in this directory.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
+
+
+CMake Error in IMPORTED_GLOBAL/CMakeLists.txt:
+  IMPORTED_GLOBAL property can't be set to FALSE on targets
+  \(\"ImportedSubdirTarget2\"\)
+
+
+
+CMake Error at IMPORTED_GLOBAL.cmake:52 \(set_property\):
+  Attempt to promote imported target \"ImportedSubdirTarget2\" to global scope
+  \(by setting IMPORTED_GLOBAL\) which is not built in this directory.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)$