From 08c7ff99e13890ed19b864e7ebfea7167eb83842 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Storsj=C3=B6?= <martin@martin.st>
Date: Mon, 28 Oct 2019 10:11:05 +0200
Subject: [PATCH] [libunwind] [Windows] Add a log message if EnumProcessModules
 fails

Differential Revision: https://reviews.llvm.org/D69504
---
 libunwind/src/AddressSpace.hpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libunwind/src/AddressSpace.hpp b/libunwind/src/AddressSpace.hpp
index 908c898d7403..db67df4dc80a 100644
--- a/libunwind/src/AddressSpace.hpp
+++ b/libunwind/src/AddressSpace.hpp
@@ -433,8 +433,12 @@ inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr,
   HANDLE process = GetCurrentProcess();
   DWORD needed;
 
-  if (!EnumProcessModules(process, mods, sizeof(mods), &needed))
+  if (!EnumProcessModules(process, mods, sizeof(mods), &needed)) {
+    DWORD err = GetLastError();
+    _LIBUNWIND_TRACE_UNWINDING("findUnwindSections: EnumProcessModules failed, "
+                               "returned error %d", (int)err);
     return false;
+  }
 
   for (unsigned i = 0; i < (needed / sizeof(HMODULE)); i++) {
     PIMAGE_DOS_HEADER pidh = (PIMAGE_DOS_HEADER)mods[i];