MSYS2-packages/gdb/0004-7.8-symtab-cygwin.patch
2023-04-28 13:02:30 +03:00

69 lines
2.5 KiB
Diff

From 1b1aae4d607d0c5d0f6e8005d6280a282413dad8 Mon Sep 17 00:00:00 2001
From: Jon Turney <jon.turney@dronecode.org.uk>
Date: Sun, 24 Jul 2016 18:18:10 +0100
Subject: [PATCH 4/6] 7.8-symtab-cygwin
See https://sourceware.org/ml/gdb-patches/2002-03/msg00557.html
---
gdb/symtab.c | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/gdb/symtab.c b/gdb/symtab.c
index f2b1a14e006..fafe0b7dfc8 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -864,6 +864,10 @@ create_demangled_names_hash (struct objfile_per_bfd_storage *per_bfd)
free_demangled_name_entry, xcalloc, xfree));
}
+#ifdef __CYGWIN__
+#define LINKER_SYMBOLS_HAVE_WIN32_STDCALL_ARG_SIZES (1)
+#endif
+
/* See symtab.h */
gdb::unique_xmalloc_ptr<char>
@@ -873,6 +877,39 @@ symbol_find_demangled_name (struct general_symbol_info *gsymbol,
gdb::unique_xmalloc_ptr<char> demangled;
int i;
+ /* On Windows, some functions use the `stdcall' calling convention,
+ in which the callee is expected to pop the arguments off the
+ stack. Normally, the caller takes care of this, because only the
+ caller knows how many arguments it really passed. To avoid
+ confusion, the linker symbols for `stdcall' functions have names
+ with a suffix "@N" attached to them, where "N" is the number of
+ bytes they'll pop. That way, if a caller thinks some `stdcall'
+ function `foo' expects M argument bytes, but the definition of
+ `foo' expects N argument bytes, N != M, then the call will be a
+ reference to `foo@M', but the definition will have a linker
+ symbol `foo@N', and you'll get a link-time `symbol not found'
+ error, instead of a crash at run-time.
+
+ (Note how this fails to address calls through function pointers,
+ since the byte count isn't part of the function pointer's type.
+ Go, Microsoft!)
+
+ Whatever. But our demangler doesn't like that '@N' suffix, so we
+ need to strip it off. */
+ if (LINKER_SYMBOLS_HAVE_WIN32_STDCALL_ARG_SIZES)
+ {
+ char *arg_byte_suffix = strchr (mangled, '@');
+ if (arg_byte_suffix)
+ {
+ int prefix_len = arg_byte_suffix - mangled;
+ char *mangled_sans_suffix = (char *)(alloca (prefix_len + 1));
+ memcpy (mangled_sans_suffix, mangled, prefix_len);
+ mangled_sans_suffix[prefix_len] = '\0';
+
+ mangled = mangled_sans_suffix;
+ }
+ }
+
if (gsymbol->language () == language_unknown)
gsymbol->m_language = language_auto;
--
2.40.0.windows.1