Fix potential invalid reset of CMAKE_FIND_LIBRARY_PREFIXES on MSVC.
- gflags_report_not_found() calls gflags_reset_find_library_prefix()
and we only reset CMAKE_FIND_LIBRARY_PREFIXES when performing a manual
search for gflags, but gflags_report_not_found() is also used
before the manual search when searching for an exported gflags target.
- As such, it was possible that we could have cleared
CMAKE_FIND_LIBRARY_PREFIXES rather than reset it if
gflags_report_not_found() was invoked during the exported target
search.
- This patch prevents this possibility by verifying that the cached
version of CMAKE_FIND_LIBRARY_PREFIXES exists before updating it.
Change-Id: I07528ae5f197a366c7da342196b3e977f9a1fc93
diff --git a/cmake/FindGflags.cmake b/cmake/FindGflags.cmake
index 6587089..8f5cd3c 100644
--- a/cmake/FindGflags.cmake
+++ b/cmake/FindGflags.cmake
@@ -85,9 +85,9 @@
# Reset CALLERS_CMAKE_FIND_LIBRARY_PREFIXES to its value when FindGflags was
# invoked, necessary for MSVC.
macro(GFLAGS_RESET_FIND_LIBRARY_PREFIX)
- if (MSVC)
+ if (MSVC AND CALLERS_CMAKE_FIND_LIBRARY_PREFIXES)
set(CMAKE_FIND_LIBRARY_PREFIXES "${CALLERS_CMAKE_FIND_LIBRARY_PREFIXES}")
- endif (MSVC)
+ endif()
endmacro(GFLAGS_RESET_FIND_LIBRARY_PREFIX)
# Called if we failed to find gflags or any of it's required dependencies,
