[PATCH] Fix build failure with boost 1.53

[Vincent Cheng]

0 A.D. currently fails to build on Debian/Ubuntu with boost 1.53 (also filed as Debian bug ​#709570). Please consider applying the following patch to fix this.

--- a/build/premake/extern_libs4.lua
+++ b/build/premake/extern_libs4.lua
@@ -242,7 +242,7 @@
 				-- The following are not strictly link dependencies on all systems, but
 				-- are included for compatibility with different versions of Boost
 				android_names = { "boost_filesystem-gcc-mt", "boost_system-gcc-mt" },
-				unix_names = { "boost_filesystem-mt", "boost_system-mt" },
+				unix_names = { "boost_filesystem", "boost_system" },
 				bsd_names = { "boost_filesystem", "boost_system" },
 			})
 		end,
@@ -251,7 +251,7 @@
 		link_settings = function()
 			add_default_links({
 				android_names = { "boost_signals-gcc-mt" },
-				unix_names = { "boost_signals-mt" },
+				unix_names = { "boost_signals" },
 				bsd_names = { "boost_signals" },
 			})
 		end,

[historic_bruno]

IMO this will have to be patched on a per-distro basis, it's already listed as a known problem in build instructions for Slackware. Unfortunately fixing it for you will break it for others. (A situation where it would be nice to have a more robust build system like CMake, but that's a lot of work)

[Markus]

Things like this should be handled by the build system, so I think we should fix this ;)

I think its not related to the boost version, so we need to check if the -mt library exists and then decide to which we try to link.

premake has a function os.findlib that I tried. It kind of worked but leper noted that the function included in the currently used premake has some features missing. It will try to lookup /etc/ld.so.conf for possible locations, but will not honour "include". At least OpenBSD does not even have this file but a binary equivalent. (Needs to call ldconfig to get a useable output.)

So we would need to insert our own findlib (use stable head... or at least that function).

[Markus]

use (working!) findlib to decide if -mt library exists and should be used

[Markus]

("premake4 embed" is needed for the changes to take effect!)

[historic_bruno]

Replying to Markus:

premake has a function os.findlib that I tried.

Nice! I didn't know that existed, maybe it would come in handy for some of our other libs.

It may be time to consider upgrading Premake. As it stands, we haven't introduced too many differences from the original 4.3 import in r9828. It wouldn't be the most fun task in the world, but we could go through and verify each change is still needed or has been fixed upstream, then upgrade to ​premake-stable. It takes A LOT of testing, each OS and compiler we support with and without PCH, and the tests must still compile and work. Off hand, the only other thing I know we would gain is VS2012 support which was added recently.

[leper]

os.findlib works after a small change on OpenBSD too (in parse_ld_so_conf() add

local file = io.open("/etc/ld.so.conf")
if file == nil then
  return dict
end

before the io.lines() call and replace the parameter/filename in that call with file. Also your patch misses the addition of os._is64bit().

I agree that upgrading premake to premake-stable (or what will hopefully become 4.4 in the future) wouldn't be the worst decision to be made.

Also see #1518 related to upgrading/differences from 4.3.

[Markus]

update os.findlib (slightly modified premake head)

[leper]

In 13512:

Use os.findlib to find boost. Patch by Markus. Fixes #1938. Refs #1518.

[leper]

Thanks for the patch.

[ben]

In 13514:

Fixes OS X build failing to find Boost libs, refs #1938