From 8e4acb82f71ad4effec8895b8fc957189ce95933 Mon Sep 17 00:00:00 2001
From: Petr Hosek <phosek@google.com>
Date: Wed, 19 Aug 2020 10:33:03 -0700
Subject: [PATCH] [CMake] Fix OCaml build failure because of absolute path in
 system libs

D85820 introduced a full path in the LLVM_SYSTEM_LIBS property of the
LLVMSupport target, which made the OCaml bindings fail to build, since
they use -l [system_lib] flags for every lib in LLVM_SYSTEM_LIBS, which
cannot work with absolute paths.

This patch solves the issue in a similar vain as ZLIB does it: it adds
the full library path to imported_libs, and adds a stripped down version
without directories, lib prefix and lib suffix to system_libs

In the future we should probably make some changes to LLVM_SYSTEM_LIBS,
since both zlib and ncurses do not necessarily have to be system libs
anymore due to the find_package / find_library bits introduced in
D85820 and D79219.

Patch By: haampie

Differential Revision: https://reviews.llvm.org/D86134
---
 llvm/lib/Support/CMakeLists.txt | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/llvm/lib/Support/CMakeLists.txt b/llvm/lib/Support/CMakeLists.txt
index b895f02..42ee6d6 100644
--- a/llvm/lib/Support/CMakeLists.txt
+++ b/llvm/lib/Support/CMakeLists.txt
@@ -2,6 +2,15 @@ if(LLVM_ENABLE_ZLIB)
   set(imported_libs ZLIB::ZLIB)
 endif()
 
+function(get_system_libname libpath libname)
+  get_filename_component(libpath ${libpath} NAME)
+  string(REPLACE ";" "|" PREFIXES "${CMAKE_FIND_LIBRARY_PREFIXES}")
+  string(REPLACE ";" "|" SUFFIXES "${CMAKE_FIND_LIBRARY_SUFFIXES}")
+  STRING(REGEX REPLACE "^(${PREFIXES})" "" libpath ${libpath})
+  STRING(REGEX REPLACE "(${SUFFIXES})$" "" libpath ${libpath})
+  set(${libname} "${libpath}" PARENT_SCOPE)
+endfunction()
+
 if( MSVC OR MINGW )
   # libuuid required for FOLDERID_Profile usage in lib/Support/Windows/Path.inc.
   # advapi32 required for CryptAcquireContextW in lib/Support/Windows/Path.inc.
@@ -22,7 +31,7 @@ elseif( CMAKE_HOST_UNIX )
     set(system_libs ${system_libs} ${Backtrace_LIBFILE})
   endif()
   if( LLVM_ENABLE_TERMINFO )
-    set(system_libs ${system_libs} ${TERMINFO_LIB})
+    set(imported_libs ${imported_libs} "${TERMINFO_LIB}")
   endif()
   if( LLVM_ENABLE_THREADS AND (HAVE_LIBATOMIC OR HAVE_CXX_LIBATOMICS64) )
     set(system_libs ${system_libs} atomic)
@@ -206,20 +215,15 @@ if(LLVM_ENABLE_ZLIB)
   if(NOT zlib_library)
     get_property(zlib_library TARGET ZLIB::ZLIB PROPERTY LOCATION)
   endif()
-  get_filename_component(zlib_library ${zlib_library} NAME)
-  if(CMAKE_STATIC_LIBRARY_PREFIX AND CMAKE_STATIC_LIBRARY_SUFFIX AND
-      zlib_library MATCHES "^${CMAKE_STATIC_LIBRARY_PREFIX}.*${CMAKE_STATIC_LIBRARY_SUFFIX}$")
-    STRING(REGEX REPLACE "^${CMAKE_STATIC_LIBRARY_PREFIX}" "" zlib_library ${zlib_library})
-    STRING(REGEX REPLACE "${CMAKE_STATIC_LIBRARY_SUFFIX}$" "" zlib_library ${zlib_library})
-  endif()
-  if(CMAKE_SHARED_LIBRARY_PREFIX AND CMAKE_SHARED_LIBRARY_SUFFIX AND
-      zlib_library MATCHES "^${CMAKE_SHARED_LIBRARY_PREFIX}.*${CMAKE_SHARED_LIBRARY_SUFFIX}$")
-    STRING(REGEX REPLACE "^${CMAKE_SHARED_LIBRARY_PREFIX}" "" zlib_library ${zlib_library})
-    STRING(REGEX REPLACE "${CMAKE_SHARED_LIBRARY_SUFFIX}$" "" zlib_library ${zlib_library})
-  endif()
+  get_system_libname(${zlib_library} zlib_library)
   set(llvm_system_libs ${llvm_system_libs} "${zlib_library}")
 endif()
 
+if(LLVM_ENABLE_TERMINFO)
+  get_system_libname(${TERMINFO_LIB} terminfo_library)
+  set(llvm_system_libs ${llvm_system_libs} "${terminfo_library}")
+endif()
+
 set_property(TARGET LLVMSupport PROPERTY LLVM_SYSTEM_LIBS "${llvm_system_libs}")
 
 if(LLVM_WITH_Z3)
-- 
2.7.4