From 9a2a7c240f2e659ff4bc1717747f1bc55ebcf7c1 Mon Sep 17 00:00:00 2001
From: Chris Smowton <chris@smowton.net>
Date: Wed, 1 Aug 2018 17:22:45 +0100
Subject: [PATCH] Switch version.cpp from a rule product to a byproduct

As a rule product it will only be created once; as a byproduct the target will always be executed,
resulting in version.cpp being regenerated when additional commits are made, and yet util.a will
correctly be sequenced behind it.

This corrects the reverted PR #2657, which did not note version.cpp as a byproduct (hence a generated
file), which meant version.cpp would be disregarded as a missing source file on the initial build.
---
 src/util/CMakeLists.txt | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/util/CMakeLists.txt b/src/util/CMakeLists.txt
index 2100c47a543..4ae6f1ff10f 100644
--- a/src/util/CMakeLists.txt
+++ b/src/util/CMakeLists.txt
@@ -30,8 +30,9 @@ endif()
 
 file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/version.cpp.in
   "const char *CBMC_VERSION=\"@CBMC_RELEASE@ (@GIT_INFO@)\";\n")
-add_custom_command(
-  OUTPUT version.cpp
+add_custom_target(
+  generate_version_cpp
+  BYPRODUCTS version.cpp
   COMMAND ${CMAKE_COMMAND}
     -D CBMC_SOURCE_DIR=${CBMC_SOURCE_DIR}
     -D CUR=${CMAKE_CURRENT_BINARY_DIR}
@@ -42,6 +43,8 @@ add_library(util
   ${sources}
   version.cpp)
 
+add_dependencies(util generate_version_cpp)
+
 generic_includes(util)
 
 target_link_libraries(util big-int langapi)