From c20ec3a443668ab7047a383958e1b2d9f687bbf0 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 31 Mar 2021 11:38:41 +0200
Subject: [PATCH 24/N] Do not show Error dialogs by default

In https://github.com/msys2/msys2-runtime/pull/18, we discussed a change
that would allow default Windows error handling of spawned processes to
kick in (such as registered JIT debuggers). We even agreed that it would
make sense to hide this functionality behind a flag, `winjitdebug`.

However, when this got upstreamed as 21ec498d7f (cygwin: use
CREATE_DEFAULT_ERROR_MODE in spawn, 2020-12-09), that flag was deemed
unnecessary.

But it would appear that it _is_ necessary: As reported in
https://github.com/msys2/MSYS2-packages/pull/2414#issuecomment-810841296
this new behavior is pretty disruptive e.g. in CI scenarios.

So let's introduce that `winjitdebug` flag (settable via the environment
variable `MSYS`) at long last.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 winsup/cygwin/environ.cc | 1 +
 winsup/cygwin/globals.cc | 1 +
 winsup/cygwin/spawn.cc   | 2 +-
 3 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/winsup/cygwin/environ.cc b/winsup/cygwin/environ.cc
index daaa1ec..f4e2c68 100644
--- a/winsup/cygwin/environ.cc
+++ b/winsup/cygwin/environ.cc
@@ -128,6 +128,7 @@ static struct parse_thing
   {"winsymlinks", {func: set_winsymlinks}, isfunc, NULL, {{0}, {0}}},
   {"disable_pcon", {&disable_pcon}, setbool, NULL, {{false}, {true}}},
   {"enable_pcon", {&disable_pcon}, setnegbool, NULL, {{true}, {false}}},
+  {"winjitdebug", {&winjitdebug}, setbool, NULL, {{false}, {true}}},
   {NULL, {0}, setdword, 0, {{0}, {0}}}
 };
 
diff --git a/winsup/cygwin/globals.cc b/winsup/cygwin/globals.cc
index b4a0c87..5c111ab 100644
--- a/winsup/cygwin/globals.cc
+++ b/winsup/cygwin/globals.cc
@@ -75,6 +75,7 @@ bool reset_com;
 bool wincmdln = true;
 winsym_t allow_winsymlinks = WSYM_deepcopy;
 bool disable_pcon = true;
+bool winjitdebug = false;
 
 bool NO_COPY in_forkee;
 
diff --git a/winsup/cygwin/spawn.cc b/winsup/cygwin/spawn.cc
index 4f28335..bc9dc5a 100644
--- a/winsup/cygwin/spawn.cc
+++ b/winsup/cygwin/spawn.cc
@@ -460,7 +460,7 @@ child_info_spawn::worker (const char *prog_arg, const char *const *argv,
 	 get the default error mode instead of inheriting the mode Cygwin
 	 uses.  This allows things like Windows Error Reporting/JIT debugging
 	 to work with processes launched from a Cygwin shell. */
-      if (!real_path.iscygexec ())
+      if (winjitdebug && !real_path.iscygexec ())
 	c_flags |= CREATE_DEFAULT_ERROR_MODE;
 
       /* We're adding the CREATE_BREAKAWAY_FROM_JOB flag here to workaround
