Introduce CMAKE_STAGING_PREFIX variable.

This variable can be useful in cross-compiling contexts where the
sysroot is read-only or where the sysroot should otherwise remain
pristine.

If the new CMAKE_STAGING_PREFIX variable is set, it is used instead
of CMAKE_INSTALL_PREFIX when generating the installation rules in
cmake_install.cmake.

This way, the CMAKE_INSTALL_PREFIX variable
always refers to the installation prefix on the target device, regardless
of whether host==target.

If any -rpath paths passed to the linker contain the CMAKE_STAGING_PREFIX,
the matching path fragments are replaced with the CMAKE_INSTALL_PREFIX.
Matching paths in the -rpath-link are not transformed.

The cross-prefix usr-move workaround is assumed not to require extension
regarding CMAKE_STAGING_PREFIX. The staging area is a single prefix, so
there is no scope for cross-prefix symlinks. The CMAKE_INSTALL_PREFIX
is still used to determine the workaround path, and that variable
remains the relevant one even if CMAKE_STAGING_PREFIX is used. If the
generated export files are deployed to the target, the workaround
will still be in place, and still be employed if required.

1 files changed, 6 insertions, 1 deletions

diff --git a/Source/cmFindCommon.cxx b/Source/cmFindCommon.cxx
index 8c42811..e8c8da3 100644
--- a/Source/cmFindCommon.cxx
+++ b/Source/cmFindCommon.cxx
@@ -165,6 +165,9 @@ void cmFindCommon::RerootPaths(std::vector<std::string>& paths)
     cmSystemTools::ConvertToUnixSlashes(*ri);
     }
 
+  const char* stagePrefix =
+      this->Makefile->GetDefinition("CMAKE_STAGING_PREFIX");
+
   // Copy the original set of unrooted paths.
   std::vector<std::string> unrootedPaths = paths;
   paths.clear();
@@ -179,7 +182,9 @@ void cmFindCommon::RerootPaths(std::vector<std::string>& paths)
       // already inside.  Skip the unrooted path if it is relative to
       // a user home directory or is empty.
       std::string rootedDir;
-      if(cmSystemTools::IsSubDirectory(ui->c_str(), ri->c_str()))
+      if(cmSystemTools::IsSubDirectory(ui->c_str(), ri->c_str())
+          || (stagePrefix
+            && cmSystemTools::IsSubDirectory(ui->c_str(), stagePrefix)))
         {
         rootedDir = *ui;
         }