From d3afdc957b384de058fcf6bc7eb05d3efbe2199f Mon Sep 17 00:00:00 2001
From: Dan Liew <daniel.liew@imperial.ac.uk>
Date: Mon, 21 Mar 2016 19:33:50 +0000
Subject: [PATCH] [CMake] Fix issue #522

Previously tracing could be disabled and was not enabled by default in a
debug build. This isn't desirable but I had avoided fixing it because
enabling tracing in debug mode would be confusing because
``ENABLE_TRACING`` could be set to off but tracing would be enabled
anyway.

I have resolved this by renaming the option from ``ENABLE_TRACING`` to
``ENABLE_TRACING_FOR_NON_DEBUG``. The semantics of the optiona are now
that it will enable tracing in non-debug builds. I have also added code
to ensure that tracing is always enabled in debug builds.

Whilst I was here I also fixed how ``option()`` was being used. The
default value and comment were in the wrong order.
---
 CMakeLists.txt  | 8 +++++---
 README-CMake.md | 2 +-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d33f352e1..c3dec71d6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -289,12 +289,14 @@ endif()
 ################################################################################
 # Tracing
 ################################################################################
-option(ENABLE_TRACING OFF "Enable tracing")
-if (ENABLE_TRACING)
+option(ENABLE_TRACING_FOR_NON_DEBUG "Enable tracing in non-debug builds." OFF)
+if (ENABLE_TRACING_FOR_NON_DEBUG)
   list(APPEND Z3_COMPONENT_CXX_DEFINES "-D_TRACE")
+else()
+  # Tracing is always enabled in debug builds
+  list(APPEND Z3_COMPONENT_CXX_DEFINES $<$<CONFIG:Debug>:_TRACE>)
 endif()
 # Should we always enable tracing when doing a debug build?
-#list(APPEND Z3_COMPONENT_CXX_DEFINES $<$<CONFIG:Debug>:_TRACE>)
 
 ################################################################################
 # Postion indepdent code
diff --git a/README-CMake.md b/README-CMake.md
index 47cc70332..47ec11a7c 100644
--- a/README-CMake.md
+++ b/README-CMake.md
@@ -266,7 +266,7 @@ The following useful options can be passed to CMake whilst configuring.
 * ``CMAKE_INSTALL_LIBDIR`` - STRING. The path to install z3 libraries (relative to ``CMAKE_INSTALL_PREFIX``), e.g. ``lib``.
 * ``CMAKE_INSTALL_PREFIX`` - STRING. The install prefix to use (e.g. ``/usr/local/``).
 * ``CMAKE_INSTALL_PYTHON_PKG_DIR`` - STRING. The path to install the z3 python bindings. This can be relative (to ``CMAKE_INSTALL_PREFIX``) or absolute.
-* ``ENABLE_TRACING`` - BOOL. If set to ``TRUE`` enable tracing, if set to ``FALSE`` disable tracing.
+* ``ENABLE_TRACING_FOR_NON_DEBUG`` - BOOL. If set to ``TRUE`` enable tracing in non-debug builds, if set to ``FALSE`` disable tracing in non-debug builds. Note in debug builds tracing is always enabled.
 * ``BUILD_LIBZ3_SHARED`` - BOOL. If set to ``TRUE`` build libz3 as a shared library otherwise build as a static library.
 * ``ENABLE_EXAMPLE_TARGETS`` - BOOL. If set to ``TRUE`` add the build targets for building the API examples.
 * ``USE_OPENMP`` - BOOL. If set to ``TRUE`` and OpenMP support is detected build with OpenMP support.