From 2c5e0b8b981dc9d1ea575037b9befa8c3b6102b8 Mon Sep 17 00:00:00 2001
From: Oscar Fuentes <ofv@wanadoo.es>
Date: Sun, 9 Jan 2011 14:34:39 +0000
Subject: [PATCH] Rewrite handling of LLVM_ENABLE_PIC. It was being processed
 after config.h was generated, so it had no effect on it.

Thanks to arrowdodger for pointing out this and a tentative patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123119 91177308-0d34-0410-b5e6-96231b3b80d8
---
 CMakeLists.txt                     | 32 ++++++++++++++++--------------
 cmake/config-ix.cmake              |  7 ++-----
 include/llvm/Config/config.h.cmake |  2 +-
 3 files changed, 20 insertions(+), 21 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5e27c6f82e4..7daaa82eef4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -195,27 +195,29 @@ else(WIN32)
   endif(UNIX)
 endif(WIN32)
 
-include(config-ix)
-
 option(LLVM_ENABLE_PIC "Build Position-Independent Code" ON)
 
-set(ENABLE_PIC 0)
 if( LLVM_ENABLE_PIC )
- if( XCODE )
-   # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
-   # know how to disable this, so just force ENABLE_PIC off for now.
-   message(STATUS "Warning: -fPIC not supported with Xcode.")
- else( XCODE )
-   if( SUPPORTS_FPIC_FLAG )
+  if( XCODE )
+    # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
+    # know how to disable this, so just force ENABLE_PIC off for now.
+    message(WARNING "-fPIC not supported with Xcode.")
+  elseif( WIN32 )
+    # On Windows all code is PIC. MinGW warns if -fPIC is used.
+  else()
+    include(CheckCXXCompilerFlag)
+    check_cxx_compiler_flag("-fPIC" SUPPORTS_FPIC_FLAG)
+    if( SUPPORTS_FPIC_FLAG )
       message(STATUS "Building with -fPIC")
-      add_llvm_definitions(-fPIC)
-      set(ENABLE_PIC 1)
-   else( SUPPORTS_FPIC_FLAG )
-      message(STATUS "Warning: -fPIC not supported.")
-   endif()
- endif()
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC")
+    else( SUPPORTS_FPIC_FLAG )
+      message(WARNING "-fPIC not supported.")
+    endif()
+  endif()
 endif()
 
+include(config-ix)
+
 set( CMAKE_RUNTIME_OUTPUT_DIRECTORY ${LLVM_TOOLS_BINARY_DIR} )
 set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib )
 set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib )
diff --git a/cmake/config-ix.cmake b/cmake/config-ix.cmake
index 27f2964038b..f0e11767e34 100755
--- a/cmake/config-ix.cmake
+++ b/cmake/config-ix.cmake
@@ -162,12 +162,9 @@ llvm_find_program(dotty)
 # Define LLVM_MULTITHREADED if gcc atomic builtins exists.
 include(CheckAtomic)
 
+set(ENABLE_PIC ${LLVM_ENABLE_PIC})
+
 include(CheckCXXCompilerFlag)
-# On windows all code is position-independent and mingw warns if -fPIC
-# is in the command-line.
-if( NOT WIN32 )
-  check_cxx_compiler_flag("-fPIC" SUPPORTS_FPIC_FLAG)
-endif()
 
 check_cxx_compiler_flag("-Wno-variadic-macros" SUPPORTS_NO_VARIADIC_MACROS_FLAG)
 
diff --git a/include/llvm/Config/config.h.cmake b/include/llvm/Config/config.h.cmake
index 4ebae94944e..255816ac230 100644
--- a/include/llvm/Config/config.h.cmake
+++ b/include/llvm/Config/config.h.cmake
@@ -31,7 +31,7 @@
 #define CXX_INCLUDE_64BIT_DIR "${CXX_INCLUDE_64BIT_DIR}"
 
 /* Define if position independent code is enabled */
-#cmakedefine ENABLE_PIC ${ENABLE_PIC}
+#cmakedefine ENABLE_PIC
 
 /* Define if threads enabled */
 #cmakedefine ENABLE_THREADS ${ENABLE_THREADS}