From f083da4c1efb0d897a89f079bfcc25401d9da513 Mon Sep 17 00:00:00 2001
From: levlam <levlam@telegram.org>
Date: Sat, 9 Jul 2022 23:40:22 +0300
Subject: [PATCH] Ignore CMAKE_INSTALL_PREFIX in pkgconfig, if
 CMAKE_INSTALL_*DIR is absolute.

---
 CMake/GeneratePkgConfig.cmake | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/CMake/GeneratePkgConfig.cmake b/CMake/GeneratePkgConfig.cmake
index b9154de13..afbe06ac6 100644
--- a/CMake/GeneratePkgConfig.cmake
+++ b/CMake/GeneratePkgConfig.cmake
@@ -64,6 +64,18 @@ function(generate_pkgconfig TARGET DESCRIPTION)
     set(LIBRARIES "Libs.private:${LIBRARIES}\n")
   endif()
 
+  if (IS_ABSOLUTE "${CMAKE_INSTALL_INCLUDEDIR}")
+    set(PKGCONFIG_INCLUDEDIR "${CMAKE_INSTALL_INCLUDEDIR}")
+  else()
+    set(PKGCONFIG_INCLUDEDIR "\${prefix}/${CMAKE_INSTALL_INCLUDEDIR}")
+  endif()
+
+  if (IS_ABSOLUTE "${CMAKE_INSTALL_LIBDIR}")
+    set(PKGCONFIG_LIBDIR "${CMAKE_INSTALL_LIBDIR}")
+  else()
+    set(PKGCONFIG_LIBDIR "\${prefix}/${CMAKE_INSTALL_LIBDIR}")
+  endif()
+
   file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/pkgconfig")
   file(GENERATE OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/pkgconfig/${TARGET}.pc" CONTENT
 "prefix=${PREFIX}
@@ -72,8 +84,8 @@ Name: ${TARGET}
 Description: ${DESCRIPTION}
 Version: ${PROJECT_VERSION}
 
-CFlags: -I\"\${prefix}/${CMAKE_INSTALL_INCLUDEDIR}\"
-Libs: -L\"\${prefix}/${CMAKE_INSTALL_LIBDIR}\" -l${TARGET}
+CFlags: -I\"${PKGCONFIG_INCLUDEDIR}\"
+Libs: -L\"${PKGCONFIG_LIBDIR}\" -l${TARGET}
 ${REQUIRES}${LIBRARIES}")
 
   install(FILES "${CMAKE_CURRENT_BINARY_DIR}/pkgconfig/${TARGET}.pc" DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig")