From ff7402abcd4cb88a2482e085df513afd6512ca30 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi>
Date: Sun, 15 Mar 2026 13:20:43 +0200
Subject: [PATCH] fix PLT unwinding and add core dump tests

---
 nativeunwind/elfunwindinfo/elfehframe_x86.go  |  4 +--
 .../testdata/amd64/debian-echo-plt1.json      | 29 +++++++++++++++++++
 .../testdata/amd64/debian-echo-plt2.json      | 29 +++++++++++++++++++
 3 files changed, 60 insertions(+), 2 deletions(-)
 create mode 100644 tools/coredump/testdata/amd64/debian-echo-plt1.json
 create mode 100644 tools/coredump/testdata/amd64/debian-echo-plt2.json

diff --git a/nativeunwind/elfunwindinfo/elfehframe_x86.go b/nativeunwind/elfunwindinfo/elfehframe_x86.go
index a04f4bde5..fb060b66e 100644
--- a/nativeunwind/elfunwindinfo/elfehframe_x86.go
+++ b/nativeunwind/elfunwindinfo/elfehframe_x86.go
@@ -169,7 +169,7 @@ func (regs *vmRegs) getUnwindInfoX86() sdtypes.UnwindInfo {
 		info.BaseReg = getUnwinderRegX86(regs.cfa.reg)
 		info.Param = int32(regs.cfa.off)
 	case regExprPLT:
-		info.Flags = support.UnwindFlagCommand
+		info.Flags |= support.UnwindFlagCommand
 		info.Param = support.UnwindCommandPLT
 	case regExprRegDeref:
 		reg, _, off, off2 := splitOff(regs.cfa.off)
@@ -184,7 +184,7 @@ func (regs *vmRegs) getUnwindInfoX86() sdtypes.UnwindInfo {
 			}
 		}
 	}
-	if info.BaseReg == support.UnwindRegInvalid {
+	if info.Flags&support.UnwindFlagCommand == 0 && info.BaseReg == support.UnwindRegInvalid {
 		return sdtypes.UnwindInfoInvalid
 	}
 	return info
diff --git a/tools/coredump/testdata/amd64/debian-echo-plt1.json b/tools/coredump/testdata/amd64/debian-echo-plt1.json
new file mode 100644
index 000000000..db71b5369
--- /dev/null
+++ b/tools/coredump/testdata/amd64/debian-echo-plt1.json
@@ -0,0 +1,29 @@
+{
+  "coredump-ref": "898161f0dac2f375b028692591093e37bb60a2a43741038d7d4e27ecda49bb4a",
+  "threads": [
+    {
+      "lwp": 3914,
+      "frames": [
+        "echo+0x2030",
+        "echo+0x235e",
+        "libc.so.6+0x27249",
+        "libc.so.6+0x27304",
+        "echo+0x2900"
+      ]
+    }
+  ],
+  "modules": [
+    {
+      "ref": "a049fb47554c6cde2ee452e5d87f6386abb63af7cdcae9cd0dc99fc80e0bcf35",
+      "local-path": "/usr/bin/echo"
+    },
+    {
+      "ref": "593bb1d5355658e645f36e6b1f49832691b24e177209765914e4cce51499dbb4",
+      "local-path": "/usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2"
+    },
+    {
+      "ref": "bff8750fe719e6000791b88b11747dce8772c37118d0b2348044b70819d13835",
+      "local-path": "/usr/lib/x86_64-linux-gnu/libc.so.6"
+    }
+  ]
+}
diff --git a/tools/coredump/testdata/amd64/debian-echo-plt2.json b/tools/coredump/testdata/amd64/debian-echo-plt2.json
new file mode 100644
index 000000000..3025703e1
--- /dev/null
+++ b/tools/coredump/testdata/amd64/debian-echo-plt2.json
@@ -0,0 +1,29 @@
+{
+  "coredump-ref": "8f89a4d0c0f9e552e9a67ebf6151262b8c0f8c97899257c301f3ee46ac7403ae",
+  "threads": [
+    {
+      "lwp": 3914,
+      "frames": [
+        "echo+0x203b",
+        "echo+0x235e",
+        "libc.so.6+0x27249",
+        "libc.so.6+0x27304",
+        "echo+0x2900"
+      ]
+    }
+  ],
+  "modules": [
+    {
+      "ref": "a049fb47554c6cde2ee452e5d87f6386abb63af7cdcae9cd0dc99fc80e0bcf35",
+      "local-path": "/usr/bin/echo"
+    },
+    {
+      "ref": "593bb1d5355658e645f36e6b1f49832691b24e177209765914e4cce51499dbb4",
+      "local-path": "/usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2"
+    },
+    {
+      "ref": "bff8750fe719e6000791b88b11747dce8772c37118d0b2348044b70819d13835",
+      "local-path": "/usr/lib/x86_64-linux-gnu/libc.so.6"
+    }
+  ]
+}