Support Windows 32-bit (and other smaller fixes)

Author: elsteveogrande

libcxx/include/__stacktrace/basic_stacktrace.h

@@ -7,8 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef _LIBCPP_STACKTRACE_BASIC
-#define _LIBCPP_STACKTRACE_BASIC
+#ifndef _LIBCPP_BASIC_STACKTRACE_H
+#define _LIBCPP_BASIC_STACKTRACE_H
 
 #include <__config>
 
@@ -339,4 +339,4 @@ _LIBCPP_END_NAMESPACE_STD
 
 _LIBCPP_POP_MACROS
 
-#endif // _LIBCPP_STACKTRACE_BASIC
+#endif // _LIBCPP_BASIC_STACKTRACE_H

libcxx/include/__stacktrace/stacktrace_entry.h

@@ -7,8 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef _LIBCPP_STACKTRACE_ENTRY
-#define _LIBCPP_STACKTRACE_ENTRY
+#ifndef _LIBCPP_STACKTRACE_ENTRY_H
+#define _LIBCPP_STACKTRACE_ENTRY_H
 
 #include <__config>
 
@@ -208,4 +208,4 @@ _LIBCPP_END_NAMESPACE_STD
 
 _LIBCPP_POP_MACROS
 
-#endif // _LIBCPP_STACKTRACE_ENTRY
+#endif // _LIBCPP_STACKTRACE_ENTRY_H

libcxx/src/stacktrace/impl_windows.cpp

@@ -171,8 +171,12 @@ base::current_impl(size_t skip, size_t max_depth) {
   frame.AddrPC.Offset    = ccx.Pc;
   frame.AddrStack.Offset = ccx.Sp;
   frame.AddrFrame.Offset = ccx.Fp;
+#elif defined(_M_IX86)
+  frame.AddrPC.Offset    = ccx.Eip;
+  frame.AddrStack.Offset = ccx.Esp;
+  frame.AddrFrame.Offset = ccx.Ebp;
 #else
-# warning stacktrace requires x86-64 or ARM64; returned stacktraces will be empty
+# warning unrecognized architecture; returned stacktraces will be empty
   return;
 #endif