From f9e141a006f5c1411dc88be75e00e2f929ced9f9 Mon Sep 17 00:00:00 2001
From: David Nadlinger <code@klickverbot.at>
Date: Wed, 9 Oct 2013 16:05:29 +0200
Subject: [PATCH] Prefer named tags to Git revision hashes for LDC verison.

This allows for building of release packages without
manually overriding the version string.

The --tag argument is needed to pick up un-annotated tags
as well.
---
 CMakeLists.txt                                | 17 ++++++++++++++---
 cmake/Modules/GetGitRevisionDescription.cmake |  2 +-
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b8095ea5..e77ec831 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -167,10 +167,21 @@ set(LDC_GENERATED
 # Gather source files.
 #
 include(GetGitRevisionDescription)
-get_git_head_revision(REFSPEC HASH)
-if(NOT HASH STREQUAL "GITDIR-NOTFOUND")
-    string(SUBSTRING "${HASH}" 0 6 LDC_VERSION)
+git_get_exact_tag(TAG)
+if(NOT TAG MATCHES "NOTFOUND")
+    if(TAG MATCHES "v[0-9].*")
+        # For a version tag, remove the leading 'v'.
+        string(SUBSTRING "${TAG}" 1 -1 LDC_VERSION)
+    else()
+        set(LDC_VERSION "${TAG}")
+    endif()
+else()
+    get_git_head_revision(REFSPEC HASH)
+    if(NOT HASH STREQUAL "GITDIR-NOTFOUND")
+        string(SUBSTRING "${HASH}" 0 6 LDC_VERSION)
+    endif()
 endif()
+message(STATUS "LDC version identifier: ${LDC_VERSION}")
 configure_file(driver/ldc-version.cpp.in driver/ldc-version.cpp)
 
 # Also add the header files to the build so that they are available in IDE
diff --git a/cmake/Modules/GetGitRevisionDescription.cmake b/cmake/Modules/GetGitRevisionDescription.cmake
index 1bf02300..d3d5f1eb 100644
--- a/cmake/Modules/GetGitRevisionDescription.cmake
+++ b/cmake/Modules/GetGitRevisionDescription.cmake
@@ -118,6 +118,6 @@ function(git_describe _var)
 endfunction()
 
 function(git_get_exact_tag _var)
-	git_describe(out --exact-match ${ARGN})
+	git_describe(out --exact-match --tag ${ARGN})
 	set(${_var} "${out}" PARENT_SCOPE)
 endfunction()