From 543b0de0b447226eb6ff489eeb68ae51a45f45bd Mon Sep 17 00:00:00 2001
From: jayzed80 <jzinkant@gmail.com>
Date: Fri, 30 Oct 2026 17:43:38 +0000
Subject: [PATCH] fix(eps): bitshift by the most negative integer no longer
 overflows on negation

Negating i64::MIN panicked in debug builds. Use saturating_neg, as Op::Neg already does.
---
 crates/eps/src/import/interp.rs | 2 +-
 crates/eps/src/import/tests.rs  | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/crates/eps/src/import/interp.rs b/crates/eps/src/import/interp.rs
index f4c210b9c..75f7c7d13 100644
--- a/crates/eps/src/import/interp.rs
+++ b/crates/eps/src/import/interp.rs
@@ -816,7 +816,7 @@ impl<'a> Interp<'a> {
             },
             Bitshift => {
                 let (s, v) = (self.pop_int()?, self.pop_int()?);
-                let r = if s >= 0 { v.checked_shl(s.min(63) as u32) } else { v.checked_shr((-s).min(63) as u32) };
+                let r = if s >= 0 { v.checked_shl(s.min(63) as u32) } else { v.checked_shr(s.saturating_neg().min(63) as u32) };
                 self.push(Obj::Int(r.unwrap_or(0)))?;
             }
             True => self.push(Obj::Bool(true))?,
diff --git a/crates/eps/src/import/tests.rs b/crates/eps/src/import/tests.rs
index 8f9cb5581..86fa8e35d 100644
--- a/crates/eps/src/import/tests.rs
+++ b/crates/eps/src/import/tests.rs
@@ -1400,3 +1400,10 @@ fn stored_graphics_states_use_up_the_memory_budget() {
         assert!(r.warnings.iter().any(|w| w.contains("uses too much memory")), "{body}: {:?}", r.warnings);
     }
 }
+
+/// `bitshift` by the most negative integer shifts right by everything, not a negation overflow.
+#[test]
+fn bitshift_by_the_most_negative_integer_does_not_panic() {
+    let r = read("0 0 10 10 rectfill 1 -9223372036854775808 bitshift pop -1 -9223372036854775808 bitshift pop");
+    assert_eq!(objects(&r.document).len(), 1, "{:?}", r.warnings);
+}