ENH: Add global property ALLOW_DUPLICATE_CUSTOM_TARGETS to help existing projects that depend on having duplicate custom targets. It is allowed only for Makefile generators. See bug#6348.

1 files changed, 19 insertions, 0 deletions

diff --git a/Source/cmake.cxx b/Source/cmake.cxx
index cf89a4c..84f4217 100644
--- a/Source/cmake.cxx
+++ b/Source/cmake.cxx
@@ -3322,6 +3322,25 @@ void cmake::DefineProperties(cmake *cm)
     "at the beginning of native build system generation.  "
     "This property causes it to display details of its analysis to stderr.");
 
+  cm->DefineProperty(
+    "ALLOW_DUPLICATE_CUSTOM_TARGETS", cmProperty::GLOBAL,
+    "Allow duplicate custom targets to be created.",
+    "Normally CMake requires that all targets built in a project have "
+    "globally unique names.  "
+    "This is necessary to generate meaningful project file names in "
+    "Xcode and VS IDE generators.  "
+    "It also allows the target names to be referenced unambiguously.\n"
+    "Makefile generators are capable of supporting duplicate custom target "
+    "names.  "
+    "For projects that care only about Makefile generators and do "
+    "not wish to support Xcode or VS IDE generators, one may set this "
+    "property to true to allow duplicate custom targets.  "
+    "The property allows multiple add_custom_target command calls in "
+    "*different directories* to specify the same target name.  "
+    "However, setting this property will cause non-Makefile generators "
+    "to produce an error and refuse to generate the project."
+    );
+
   cm->DefineProperty
     ("IN_TRY_COMPILE", cmProperty::GLOBAL,
      "Read-only property that is true during a try-compile configuration.",