From 0a2e27d96428e7dd0c834deb7a97033438b6dd8e Mon Sep 17 00:00:00 2001
From: Jim Grosbach <grosbach@apple.com>
Date: Mon, 10 Dec 2012 19:03:37 +0000
Subject: [PATCH] CMake: Don't run 'git svn' if there is no .git/svn directory.

If the local checkout does not have 'git svn' references set up, don't try
to use 'git svn' for version information.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169749 91177308-0d34-0410-b5e6-96231b3b80d8
---
 cmake/modules/VersionFromVCS.cmake | 82 +++++++++++++++---------------
 1 file changed, 42 insertions(+), 40 deletions(-)

diff --git a/cmake/modules/VersionFromVCS.cmake b/cmake/modules/VersionFromVCS.cmake
index d6a2ae5f45f..26314d4126d 100644
--- a/cmake/modules/VersionFromVCS.cmake
+++ b/cmake/modules/VersionFromVCS.cmake
@@ -20,49 +20,51 @@ function(add_version_info_from_vcs VERS)
   elseif( EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/.git )
     set(result "${result}git")
     # Try to get a ref-id
-    find_program(git_executable NAMES git git.exe git.cmd)
-    if( git_executable )
-      set(is_git_svn_rev_exact false)
-      execute_process(COMMAND ${git_executable} svn log --limit=1 --oneline
-                      WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
-                      TIMEOUT 5
-                      RESULT_VARIABLE git_result
-                      OUTPUT_VARIABLE git_output)
-      if( git_result EQUAL 0 )
-        string(REGEX MATCH r[0-9]+ git_svn_rev ${git_output})
-        string(LENGTH "${git_svn_rev}" rev_length)
-        math(EXPR rev_length "${rev_length}-1")
-        string(SUBSTRING "${git_svn_rev}" 1 ${rev_length} git_svn_rev_number)
-        set(SVN_REVISION ${git_svn_rev_number} PARENT_SCOPE)
-        set(git_svn_rev "-svn-${git_svn_rev}")
-
-        # Determine if the HEAD points directly at a subversion revision.
-        execute_process(COMMAND ${git_executable} svn find-rev HEAD
-                        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
-                        TIMEOUT 5
-                        RESULT_VARIABLE git_result
-                        OUTPUT_VARIABLE git_output)
+    if( EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/.git/svn )
+      find_program(git_executable NAMES git git.exe git.cmd)
+      if( git_executable )
+        set(is_git_svn_rev_exact false)
+        execute_process(COMMAND ${git_executable} svn log --limit=1 --oneline
+          WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+          TIMEOUT 5
+          RESULT_VARIABLE git_result
+          OUTPUT_VARIABLE git_output)
         if( git_result EQUAL 0 )
-          string(STRIP "${git_output}" git_head_svn_rev_number)
-          if( git_head_svn_rev_number EQUAL git_svn_rev_number )
-            set(is_git_svn_rev_exact true)
+          string(REGEX MATCH r[0-9]+ git_svn_rev ${git_output})
+          string(LENGTH "${git_svn_rev}" rev_length)
+          math(EXPR rev_length "${rev_length}-1")
+          string(SUBSTRING "${git_svn_rev}" 1 ${rev_length} git_svn_rev_number)
+          set(SVN_REVISION ${git_svn_rev_number} PARENT_SCOPE)
+          set(git_svn_rev "-svn-${git_svn_rev}")
+
+          # Determine if the HEAD points directly at a subversion revision.
+          execute_process(COMMAND ${git_executable} svn find-rev HEAD
+            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+            TIMEOUT 5
+            RESULT_VARIABLE git_result
+            OUTPUT_VARIABLE git_output)
+          if( git_result EQUAL 0 )
+            string(STRIP "${git_output}" git_head_svn_rev_number)
+            if( git_head_svn_rev_number EQUAL git_svn_rev_number )
+              set(is_git_svn_rev_exact true)
+            endif()
           endif()
+        else()
+          set(git_svn_rev "")
+        endif()
+        execute_process(COMMAND
+          ${git_executable} rev-parse --short HEAD
+          WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+          TIMEOUT 5
+          RESULT_VARIABLE git_result
+          OUTPUT_VARIABLE git_output)
+        if( git_result EQUAL 0 AND NOT is_git_svn_rev_exact )
+          string(STRIP "${git_output}" git_ref_id)
+          set(GIT_COMMIT ${git_ref_id} PARENT_SCOPE)
+          set(result "${result}${git_svn_rev}-${git_ref_id}")
+        else()
+          set(result "${result}${git_svn_rev}")
         endif()
-      else()
-        set(git_svn_rev "")
-      endif()
-      execute_process(COMMAND
-                      ${git_executable} rev-parse --short HEAD
-                      WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
-                      TIMEOUT 5
-                      RESULT_VARIABLE git_result
-                      OUTPUT_VARIABLE git_output)
-      if( git_result EQUAL 0 AND NOT is_git_svn_rev_exact )
-        string(STRIP "${git_output}" git_ref_id)
-        set(GIT_COMMIT ${git_ref_id} PARENT_SCOPE)
-        set(result "${result}${git_svn_rev}-${git_ref_id}")
-      else()
-        set(result "${result}${git_svn_rev}")
       endif()
     endif()
   endif()