From 0811990d4a6c4f95fbc4123e16b6a3d46b8c726f Mon Sep 17 00:00:00 2001
From: Jonathan G Rennison <j.g.rennison@gmail.com>
Date: Sun, 4 Sep 2022 19:41:05 +0100
Subject: [PATCH] Unix: Try using addr2line for crash log backtrace symbol
 resolution

---
 src/os/unix/crashlog_unix.cpp | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/os/unix/crashlog_unix.cpp b/src/os/unix/crashlog_unix.cpp
index 44f579a257..0128d2478f 100644
--- a/src/os/unix/crashlog_unix.cpp
+++ b/src/os/unix/crashlog_unix.cpp
@@ -540,6 +540,32 @@ class CrashLogUnix : public CrashLog {
 			void *func_addr = info.dli_saddr;
 			const char *file_name = nullptr;
 			unsigned int line_num = 0;
+			const int ptr_str_size = (2 + sizeof(void*) * 2);
+			if (dladdr_result && info.dli_fname) {
+				char *saved_buffer = buffer;
+				char addr_ptr_buffer[64];
+				seprintf(addr_ptr_buffer, lastof(addr_ptr_buffer), PRINTF_SIZEX, (char *)trace[i] - (char *)info.dli_fbase);
+				const char *args[] = {
+					"addr2line",
+					"-e",
+					info.dli_fname,
+					"-C",
+					"-i",
+					"-f",
+					"-p",
+					addr_ptr_buffer,
+					nullptr,
+				};
+				buffer += seprintf(buffer, last, " [%02i] %*p %-40s ", i, ptr_str_size, trace[i], info.dli_fname);
+				const char *buffer_start = buffer;
+				bool result = ExecReadStdout("addr2line", const_cast<char* const*>(args), buffer, last);
+				if (result && strstr(buffer_start, "??") == nullptr) {
+					while (buffer[-1] == '\n' && buffer[-2] == '\n') buffer--;
+					continue;
+				}
+				buffer = saved_buffer;
+				*buffer = 0;
+			}
 #if defined(WITH_BFD)
 			/* subtract one to get the line before the return address, i.e. the function call line */
 			sym_info_bfd bfd_info(reinterpret_cast<bfd_vma>(trace[i]) - reinterpret_cast<bfd_vma>(info.dli_fbase) - 1);
@@ -552,7 +578,6 @@ class CrashLogUnix : public CrashLog {
 			}
 #endif /* WITH_BFD */
 			bool ok = true;
-			const int ptr_str_size = (2 + sizeof(void*) * 2);
 			if (dladdr_result && func_name) {
 				int status = -1;
 				char *demangled = nullptr;