Merging r312043:

tstellar · tstellar · commit 399df16520c8 · 2017-11-15T22:26:48.000Z
------------------------------------------------------------------------ r312043 | rnk | 2017-08-29 14:44:21 -0700 (Tue, 29 Aug 2017) | 25 lines [cmake] Stop putting the revision info in LLVM_VERSION_STRING Summary: This reduces the number of build actions after a no-op commit from thousands to about six, which should be acceptable. If six actions is still too many, developers can disable the LLVM_APPEND_VC_REV cmake option. llvm-config.h is a widely included header that should rarely change. Before this patch, it would change after every re-configure. Very few users of llvm-config.h need to know the precise version, and those that do can migrate to incorporating LLVM_REVISION as provided by llvm/Support/VCSRevision.h. This should bring LLVM back to the behavior that it had before r306858 from June 30 2017. Most LLVM tools will now print a version string like "6.0.0svn" instead of "6.0.0-git-c40c2a23de4". Fixes PR34308 Reviewers: pcc, rafael, hans Subscribers: mgorny, llvm-commits Differential Revision: https://reviews.llvm.org/D37272 ------------------------------------------------------------------------ git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_50@318344 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -208,10 +208,6 @@ include(VersionFromVCS)
 option(LLVM_APPEND_VC_REV
   "Embed the version control system revision id in LLVM" ON)
 
-if( LLVM_APPEND_VC_REV )
-  add_version_info_from_vcs(PACKAGE_VERSION)
-endif()
-
 set(PACKAGE_NAME LLVM)
 set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")
 set(PACKAGE_BUGREPORT "http://llvm.org/bugs/")
diff --git a/docs/CMake.rst b/docs/CMake.rst
@@ -248,9 +248,10 @@ LLVM-specific variables
 
 **LLVM_APPEND_VC_REV**:BOOL
   Embed version control revision info (svn revision number or Git revision id).
-  This is used among other things in the LLVM version string (stored in the
-  PACKAGE_VERSION macro). For this to work cmake must be invoked before the
-  build. Defaults to ON.
+  The version info is provided by the ``LLVM_REVISION`` macro in
+  ``llvm/include/llvm/Support/VCSRevision.h``. Developers using git who don't
+  need revision info can disable this option to avoid re-linking most binaries
+  after a branch switch. Defaults to ON.
 
 **LLVM_ENABLE_THREADS**:BOOL
   Build with threads support, if available. Defaults to ON.
