build: update std/debug.zig to zig-0.15.0-dev.877+0adcfd60f

This currently requires cloning std.debug to grant access to the standard trace
dump handler. Hopefully in future this could be made public in the standard
library.

build.zig.zon

@@ -15,8 +15,8 @@
             .hash = "dizzy-1.0.0-AAAAAM1wAAAiDbx_6RwcVEOBk8p2XOu8t9WPNc3K7kBK",
         },
         .thespian = .{
-            .url = "https://github.com/neurocyte/thespian/archive/a7b2354ad2fbe9d2b3629a455f2e823b463c18eb.tar.gz",
+            .url = "https://github.com/neurocyte/thespian/archive/829a8d33e92988a51a8c51d204ec766a28c7903d.tar.gz",
-            .hash = "thespian-0.0.1-owFOjosTBgAgvY4TcT_xI30QsbU8cE_tAUu_HoxoTjMV",
+            .hash = "thespian-0.0.1-owFOjs0TBgAAed7EtHDPtpB7NBn-riNjb7Rkc7a_Voow",
         },
         .themes = .{
             .url = "https://github.com/neurocyte/flow-themes/releases/download/master-952f9f630ea9544088fd30293666ee0650b7a690/flow-themes.tar.gz",

src/main.zig

@@ -149,7 +149,10 @@ pub fn main() anyerror!void {
     }
 
     if (builtin.os.tag != .windows)
-        if (std.posix.getenv("JITDEBUG")) |_| thespian.install_debugger();
+        if (std.posix.getenv("JITDEBUG")) |_|
+            thespian.install_debugger()
+        else if (@hasDecl(renderer, "install_crash_handler"))
+            renderer.install_crash_handler();
 
     if (args.debug_wait) {
         std.debug.print("press return to start", .{});

src/renderer/vaxis/renderer.zig

@@ -118,6 +118,34 @@ pub fn panic_in_progress() bool {
     return in_panic.load(.acquire);
 }
 
+pub fn install_crash_handler() void {
+    if (!std.debug.have_segfault_handling_support) {
+        @compileError("segfault handler not supported for this target");
+    }
+    const act = std.posix.Sigaction{
+        .handler = .{ .sigaction = handle_crash },
+        .mask = std.posix.sigemptyset(),
+        .flags = (std.posix.SA.SIGINFO | std.posix.SA.RESTART),
+    };
+
+    std.posix.sigaction(std.posix.SIG.BUS, &act, null);
+    std.posix.sigaction(std.posix.SIG.SEGV, &act, null);
+    std.posix.sigaction(std.posix.SIG.ABRT, &act, null);
+    std.posix.sigaction(std.posix.SIG.FPE, &act, null);
+    std.posix.sigaction(std.posix.SIG.ILL, &act, null);
+}
+
+fn handle_crash(sig: i32, info: *const std.posix.siginfo_t, ctx_ptr: ?*anyopaque) callconv(.c) noreturn {
+    in_panic.store(true, .release);
+    const cleanup = panic_cleanup;
+    panic_cleanup = null;
+    if (cleanup) |self| {
+        self.vx.deinit(self.allocator, self.tty.anyWriter());
+        self.tty.deinit();
+    }
+    @import("std/debug.zig").handleSegfaultPosix(sig, info, ctx_ptr);
+}
+
 pub fn run(self: *Self) Error!void {
     self.vx.sgr = .legacy;
     self.vx.conpty_hacks = true;