Patch to specify the library containing terminfo symbols

[glennpj]

Summary

When compiling LLVM on Spack, I saw library linking to my system libtinfo rather than the spack built ncurses. This is because the search path in config-ix.cmake list tinfo first.

The atttached patch creates a new variable to use to specify the library that contains the tinfo symbols, and then makes sure that it is first in the list. This may need to have a conditional relationship with LLVM_ENABLE_TERMINFO but that is not done in this patch.

compiler-rt/cmake/config-ix.cmake

 
 # Look for terminfo library, used in unittests that depend on LLVMSupport.
 if(LLVM_ENABLE_TERMINFO)
-  foreach(library terminfo tinfo curses ncurses ncursesw)
+    foreach(library ${CURSES_TINFO} terminfo tinfo curses ncurses ncursesw)
     string(TOUPPER ${library} library_suffix)
     check_library_exists(
       ${library} setupterm "" COMPILER_RT_HAS_TERMINFO_${library_suffix})

llvm/CMakeLists.txt

   CACHE STRING "Set target to use for LLVM JIT or use \"host\" for automatic detection.")
 
 option(LLVM_ENABLE_TERMINFO "Use terminfo database if available." ON)
+set(CURSES_TINFO "" CACHE STRING "Set library where tinfo symbols are.")
 
 set(LLVM_ENABLE_LIBXML2 "ON" CACHE STRING "Use libxml2 if available. Can be ON, OFF, or FORCE_ON")
 

llvm/cmake/config-ix.cmake

     endif()
     if(LLVM_ENABLE_TERMINFO)
       set(HAVE_TERMINFO 0)
-      foreach(library terminfo tinfo curses ncurses ncursesw)
+      foreach(library ${CURSES_TINFO} terminfo tinfo curses ncurses ncursesw)
         string(TOUPPER ${library} library_suffix)
         check_library_exists(${library} setupterm "" HAVE_TERMINFO_${library_suffix})
         if(HAVE_TERMINFO_${library_suffix})