[llvm-branch-commits] [flang] release/20.x: [flang][runtime] Make sure to link libexecinfo if it exists (#125344) (PR #125515)

[via llvm-branch-commits]

https://github.com/llvmbot created https://github.com/llvm/llvm-project/pull/125515

Backport cb2598dda1aae5096a77bc8a9f6679ca1b350e5e

Requested by: @brad0

>From acd0c6c1774c2c2ba97c714709041f6561370447 Mon Sep 17 00:00:00 2001
From: Brad Smith <brad at comstyle.com>
Date: Mon, 3 Feb 2025 10:03:59 -0500
Subject: [PATCH] [flang][runtime] Make sure to link libexecinfo if it exists
 (#125344)

Fixes building the backtrace support on FreeBSD/NetBSD/OpenBSD/DragonFly and musl
libc with libexecinfo.

(cherry picked from commit cb2598dda1aae5096a77bc8a9f6679ca1b350e5e)
---
 flang/runtime/CMakeLists.txt | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/flang/runtime/CMakeLists.txt b/flang/runtime/CMakeLists.txt
index fbfaae9a880648..bf27a121e4d174 100644
--- a/flang/runtime/CMakeLists.txt
+++ b/flang/runtime/CMakeLists.txt
@@ -59,10 +59,15 @@ if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
     )
 endif()
 
+set(linked_libraries FortranDecimal)
+
 # function checks
 find_package(Backtrace)
 set(HAVE_BACKTRACE ${Backtrace_FOUND})
 set(BACKTRACE_HEADER ${Backtrace_HEADER})
+if(HAVE_BACKTRACE)
+  list(APPEND linked_libraries ${Backtrace_LIBRARY})
+endif()
 
 include(CheckCXXSymbolExists)
 include(CheckCXXSourceCompiles)
@@ -271,7 +276,7 @@ if (NOT DEFINED MSVC)
   add_flang_library(FortranRuntime
     ${sources}
     LINK_LIBS
-    FortranDecimal
+    ${linked_libraries}
 
     INSTALL_WITH_TOOLCHAIN
   )
@@ -279,7 +284,7 @@ else()
   add_flang_library(FortranRuntime
     ${sources}
     LINK_LIBS
-    FortranDecimal
+    ${linked_libraries}
   )
   set(CMAKE_MSVC_RUNTIME_LIBRARY MultiThreaded)
   add_flang_library(FortranRuntime.static ${sources}