From: Alexandre Ganea <alexandre.ganea@ubisoft.com>
Date: Wed, 19 Dec 2018 19:42:21 +0000 (+0000)
Subject: Re-land "Fix MSVC dependency issue between Clang-tablegen and LLVM-tablegen"
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=97a44c831115787d7651db1ba6518836e1847662;p=llvm

Re-land "Fix MSVC dependency issue between Clang-tablegen and LLVM-tablegen"
(was reverted by mistake)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349672 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/cmake/modules/TableGen.cmake b/cmake/modules/TableGen.cmake
index ee1840da6c5..3c84ae78a34 100644
--- a/cmake/modules/TableGen.cmake
+++ b/cmake/modules/TableGen.cmake
@@ -146,6 +146,12 @@ macro(add_tablegen target project)
       llvm_ExternalProject_BuildCmd(tblgen_build_cmd ${target}
                                     ${LLVM_NATIVE_BUILD}
                                     CONFIGURATION Release)
+      # Create an artificial dependency between tablegen projects, because they
+      # compile the same dependencies, thus using the same build folders.
+      # FIXME: A proper fix requires sequentially chaining tablegens.
+      if (NOT ${project} STREQUAL LLVM AND TARGET ${project}-tablegen-host)
+        add_dependencies(${project}-tablegen-host LLVM-tablegen-host)
+      endif()
       add_custom_command(OUTPUT ${${project}_TABLEGEN_EXE}
         COMMAND ${tblgen_build_cmd}
         DEPENDS CONFIGURE_LLVM_NATIVE ${target}