From 455d333233139e37b7b1a1eb447473a09c7bae80 Mon Sep 17 00:00:00 2001
From: Stephen Neuendorffer <stephen.neuendorffer@amd.com>
Date: Fri, 29 Sep 2023 15:35:54 -0700
Subject: [PATCH] Use --gcc-toolchain, instead of explicit library paths.

The petalinux sysroot has some shortcomings in the way it is
structured which prevent clang from picking the 'right' include and
library paths.  Rather than patching these individually, it's better
to use the --gcc-toolchain argument to get them all in one shot.
---
 toolchain_clang_crosscomp_arm_petalinux.cmake | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/toolchain_clang_crosscomp_arm_petalinux.cmake b/toolchain_clang_crosscomp_arm_petalinux.cmake
index c8908b6e..4657b2ab 100644
--- a/toolchain_clang_crosscomp_arm_petalinux.cmake
+++ b/toolchain_clang_crosscomp_arm_petalinux.cmake
@@ -49,14 +49,16 @@ list(APPEND CMAKE_TRY_COMPILE_PLATFORM_VARIABLES gccVer)
 
 include(toolchain_clang_crosscomp_arm)
 
-# Vitis/PetaLinux sysroot specific 
-set(CMAKE_C_FLAGS "-Wl,-z,notext -I${Sysroot}/usr/include/c++/${gccVer} -I${Sysroot}/usr/include/c++/${gccVer}/${sysrootPrefix} -B ${Sysroot}/usr/lib/${sysrootPrefix}/${gccVer} -Wl,-rpath-link=${Sysroot}/usr/lib/${sysrootPrefix}/${gccVer} --target=${gnuArch} -Wno-unused-command-line-argument -L${Sysroot}/usr/lib/${sysrootPrefix}/${gccVer}" CACHE STRING "" FORCE)
+# Vitis/PetaLinux sysroot specific
+# Explicitly specify the toolchain because the petalinux sysroot does not have /usr/include mirrored to /include.
+set(CMAKE_C_FLAGS "-Wl,-z,notext --gcc-toolchain=${Sysroot}/usr --target=${gnuArch} -Wno-unused-command-line-argument" CACHE STRING "" FORCE)
 
 # TODO: Does this need -L?
-set(CMAKE_SHARED_LINKER_FLAGS "-Wl,-z,notext -fuse-ld=lld -B ${Sysroot}/usr/lib/${sysrootPrefix}/${gccVer} -L${Sysroot}/usr/lib/${sysrootPrefix}/${gccVer}" CACHE STRING "" FORCE)
+set(CMAKE_SHARED_LINKER_FLAGS "-Wl,-z,notext -fuse-ld=lld" CACHE STRING "" FORCE)
 
 # TODO: Does this need -L?
-set(CMAKE_EXE_LINKER_FLAGS "-Wl,-z,notext -fuse-ld=lld -B ${Sysroot}/usr/lib/${sysrootPrefix}/${gccVer} -L${Sysroot}/usr/lib/${sysrootPrefix}/${gccVer}" CACHE STRING "" FORCE)
+# Force -static linking because otherwise may pickup libpthread.a instead of libpthread.so
+set(CMAKE_EXE_LINKER_FLAGS "-static -Wl,-z,notext -fuse-ld=lld" CACHE STRING "" FORCE)
 
 #set(CMAKE_C_IMPLICIT_LINK_LIBRARIES gcc_s CACHE STRING "" FORCE) 
 #set(CMAKE_CXX_IMPLICIT_LINK_LIBRARIES gcc_s CACHE STRING "" FORCE)