[cmake] Reset variable before using it

A bunch of macros use the same variable name, and since CMake macros
don't get their own scope, the value persists across macro invocations,
and we can end up exporting targets which shouldn't be exported. Clear
the variable before each use to avoid this.

Converting these macros to functions would also help, since it would
avoid the variable leaking into its parent scope, and that's something I
plan to follow up with. It won't fully address the problem, however,
since functions still inherit variables from their parent scopes, so if
someone in the parent scope just happened to use the same variable name
we'd still have the same issue.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357036 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/cmake/modules/AddLLVM.cmake b/cmake/modules/AddLLVM.cmake
index e72680c..41e2635 100644 (file)
--- a/cmake/modules/AddLLVM.cmake
+++ b/cmake/modules/AddLLVM.cmake
@@ -669,6 +669,7 @@ macro(add_llvm_library name)
         set(install_type LIBRARY)
       endif()
 
+      set(export_to_llvmexports)
       if(${name} IN_LIST LLVM_DISTRIBUTION_COMPONENTS OR
           (in_llvm_libs AND "llvm-libraries" IN_LIST LLVM_DISTRIBUTION_COMPONENTS) OR
           NOT LLVM_DISTRIBUTION_COMPONENTS)
@@ -874,6 +875,7 @@ macro(add_llvm_tool name)
 
   if ( ${name} IN_LIST LLVM_TOOLCHAIN_TOOLS OR NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
     if( LLVM_BUILD_TOOLS )
+      set(export_to_llvmexports)
       if(${name} IN_LIST LLVM_DISTRIBUTION_COMPONENTS OR
           NOT LLVM_DISTRIBUTION_COMPONENTS)
         set(export_to_llvmexports EXPORT LLVMExports)
@@ -921,6 +923,7 @@ macro(add_llvm_utility name)
   set_target_properties(${name} PROPERTIES FOLDER "Utils")
   if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
     if (LLVM_INSTALL_UTILS AND LLVM_BUILD_UTILS)
+      set(export_to_llvmexports)
       if (${name} IN_LIST LLVM_DISTRIBUTION_COMPONENTS OR
           NOT LLVM_DISTRIBUTION_COMPONENTS)
         set(export_to_llvmexports EXPORT LLVMExports)

diff --git a/cmake/modules/TableGen.cmake b/cmake/modules/TableGen.cmake
index 3c84ae7..1701a46 100644 (file)
--- a/cmake/modules/TableGen.cmake
+++ b/cmake/modules/TableGen.cmake
@@ -164,6 +164,7 @@ macro(add_tablegen target project)
   endif()
 
   if (${project} STREQUAL LLVM AND NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
+    set(export_to_llvmexports)
     if(${target} IN_LIST LLVM_DISTRIBUTION_COMPONENTS OR
         NOT LLVM_DISTRIBUTION_COMPONENTS)
       set(export_to_llvmexports EXPORT LLVMExports)