From 81f6665abb1f32a3286e3e345f3f23f6bc761075 Mon Sep 17 00:00:00 2001
From: Jan Engelhardt <jengelh@inai.de>
Date: Tue, 14 Nov 2023 22:31:06 +0100
Subject: [PATCH] build: resolve cmake processing error on Linux

Introduced by commit 959f50eb79af5b1e08b3387d33b5bf91c7c8b530
was this odd build failure:

$ cmake . && make dsda-doom-wad
-- Configuring done (1.1s)
-- Generating done (0.0s)
-- Build files have been written to: ~/dsda-doom/prboom2
[ 75%] Built target rdatawad
[100%] Built target dsda-doom-wad
$ make
[  3%] Built target rdatawad
[  4%] Built target dsda-doom-wad
src/CMakeFiles/dsda-doom.dir/build.make:3950: warning: overriding recipe for target 'dsda-doom'
src/CMakeFiles/dsda-doom.dir/build.make:3940: warning: ignoring old recipe for target 'dsda-doom'

It appears that the path suffix at some points gets a match
with /usr as an anchor. Specifying the full build path seems
to sidestep the issue.
---
 prboom2/cmake/FindLibMad.cmake | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/prboom2/cmake/FindLibMad.cmake b/prboom2/cmake/FindLibMad.cmake
index 376b10f06..ec0c14510 100644
--- a/prboom2/cmake/FindLibMad.cmake
+++ b/prboom2/cmake/FindLibMad.cmake
@@ -59,13 +59,13 @@ select_dll_configurations(LibMad)
 find_library(
   LibMad_LIBRARY_RELEASE
   NAMES mad
-  PATH_SUFFIXES ../../lib
+  PATH_SUFFIXES ${CMAKE_CURRENT_BINARY_DIR}/../../lib
 )
 
 find_library(
   LibMad_LIBRARY_DEBUG
   NAMES mad
-  PATH_SUFFIXES ../debug/lib
+  PATH_SUFFIXES ${CMAKE_CURRENT_BINARY_DIR}/../debug/lib
 )
 
 include(SelectLibraryConfigurations)