[PATCH 0/2] GCC exception codes

[PATCH 0/2] GCC exception codes

[Ken Brown]

Ken Brown (2):
  Cygwin: add header defining GCC exception codes
  Cygwin: strace: ignore GCC exceptions

 winsup/cygwin/exceptions.cc | 10 +---------
 winsup/cygwin/gcc_seh.h     | 19 +++++++++++++++++++
 winsup/utils/strace.cc      |  8 ++++++++
 3 files changed, 28 insertions(+), 9 deletions(-)
 create mode 100644 winsup/cygwin/gcc_seh.h

-- 
2.28.0

[PATCH 1/2] Cygwin: add header defining GCC exception codes

[Ken Brown]

Include it in exceptions.cc instead of defining the exception codes
there.
---
 winsup/cygwin/exceptions.cc | 10 +---------
 winsup/cygwin/gcc_seh.h     | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+), 9 deletions(-)
 create mode 100644 winsup/cygwin/gcc_seh.h

diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc
index 61406e5d1..bb7704f94 100644
--- a/winsup/cygwin/exceptions.cc
+++ b/winsup/cygwin/exceptions.cc
@@ -28,6 +28,7 @@ details. */
 #include "ntdll.h"
 #include "exception.h"
 #include "posix_timer.h"
+#include "gcc_seh.h"
 
 /* Definitions for code simplification */
 #ifdef __x86_64__
@@ -763,15 +764,6 @@ exception::handle (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT *in,
       return ExceptionContinueExecution;
 
 #ifdef __x86_64__
-/* From the GCC source file libgcc/unwind-seh.c. */
-#define STATUS_USER_DEFINED		(1U << 29)
-#define GCC_MAGIC			(('G' << 16) | ('C' << 8) | 'C')
-#define GCC_EXCEPTION(TYPE)		\
-       (STATUS_USER_DEFINED | ((TYPE) << 24) | GCC_MAGIC)
-#define STATUS_GCC_THROW		GCC_EXCEPTION (0)
-#define STATUS_GCC_UNWIND		GCC_EXCEPTION (1)
-#define STATUS_GCC_FORCED		GCC_EXCEPTION (2)
-
     case STATUS_GCC_THROW:
     case STATUS_GCC_UNWIND:
     case STATUS_GCC_FORCED:
diff --git a/winsup/cygwin/gcc_seh.h b/winsup/cygwin/gcc_seh.h
new file mode 100644
index 000000000..fb779ef73
--- /dev/null
+++ b/winsup/cygwin/gcc_seh.h
@@ -0,0 +1,19 @@
+/* gcc_seh.h: GCC exception codes.
+
+This software is a copyrighted work licensed under the terms of the
+Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+details. */
+
+#pragma once
+
+/* From the GCC source file libgcc/unwind-seh.c. */
+
+#ifdef __x86_64__
+#define STATUS_USER_DEFINED		(1U << 29)
+#define GCC_MAGIC			(('G' << 16) | ('C' << 8) | 'C')
+#define GCC_EXCEPTION(TYPE)		\
+       (STATUS_USER_DEFINED | ((TYPE) << 24) | GCC_MAGIC)
+#define STATUS_GCC_THROW		GCC_EXCEPTION (0)
+#define STATUS_GCC_UNWIND		GCC_EXCEPTION (1)
+#define STATUS_GCC_FORCED		GCC_EXCEPTION (2)
+#endif
-- 
2.28.0

[PATCH 2/2] Cygwin: strace: ignore GCC exceptions

[Ken Brown]

Any C++ app that calls 'throw' on 64-bit Cygwin results in an
exception of type STATUS_GCC_THROW (0x20474343) generated by the C++
runtime.  Don't pollute the strace output by printing information
about this and other GCC exceptions.
---
 winsup/utils/strace.cc | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/winsup/utils/strace.cc b/winsup/utils/strace.cc
index 9b6569a70..b96ad40c1 100644
--- a/winsup/utils/strace.cc
+++ b/winsup/utils/strace.cc
@@ -25,6 +25,7 @@ details. */
 #include "../cygwin/include/sys/cygwin.h"
 #include "../cygwin/include/cygwin/version.h"
 #include "../cygwin/cygtls_padsize.h"
+#include "../cygwin/gcc_seh.h"
 #include "path.h"
 #undef cygwin_internal
 #include "loadlib.h"
@@ -790,6 +791,13 @@ proc_child (unsigned mask, FILE *ofile, pid_t pid)
 	    case STATUS_BREAKPOINT:
 	    case 0x406d1388:		/* SetThreadName exception. */
 	      break;
+#ifdef __x86_64__
+	    case STATUS_GCC_THROW:
+	    case STATUS_GCC_UNWIND:
+	    case STATUS_GCC_FORCED:
+	      status = DBG_EXCEPTION_NOT_HANDLED;
+	      break;
+#endif
 	    default:
 	      status = DBG_EXCEPTION_NOT_HANDLED;
 	      if (ev.u.Exception.dwFirstChance)
-- 
2.28.0

Re: [PATCH 0/2] GCC exception codes

[Corinna Vinschen]

On Aug 20 10:55, Ken Brown via Cygwin-patches wrote:
> Ken Brown (2):
>   Cygwin: add header defining GCC exception codes
>   Cygwin: strace: ignore GCC exceptions
> 
>  winsup/cygwin/exceptions.cc | 10 +---------
>  winsup/cygwin/gcc_seh.h     | 19 +++++++++++++++++++
>  winsup/utils/strace.cc      |  8 ++++++++
>  3 files changed, 28 insertions(+), 9 deletions(-)
>  create mode 100644 winsup/cygwin/gcc_seh.h
> 
> -- 
> 2.28.0

LGTM.  Please push.


Thanks,
Corinna