1 files changed, 19 insertions, 0 deletions
diff --git a/src/math/floor.rs b/src/math/floor.rs
index b2b7605..d09f9a1 100644
--- a/src/math/floor.rs
+++ b/src/math/floor.rs
@@ -1,3 +1,4 @@
+#![allow(unreachable_code)]
 use core::f64;
 
 const TOINT: f64 = 1. / f64::EPSILON;
@@ -15,6 +16,24 @@ pub fn floor(x: f64) -> f64 {
             return unsafe { ::core::intrinsics::floorf64(x) }
         }
     }
+    #[cfg(all(target_arch = "x86", not(target_feature = "sse2")))]
+    {
+        //use an alternative implementation on x86, because the
+        //main implementation fails with the x87 FPU used by
+        //debian i386, probablly due to excess precision issues.
+        //basic implementation taken from https://github.com/rust-lang/libm/issues/219
+        use super::fabs;
+        if fabs(x).to_bits() < 4503599627370496.0_f64.to_bits() {
+            let truncated = x as i64 as f64;
+            if truncated > x {
+                return truncated - 1.0;
+            } else {
+                return truncated;
+            }
+        } else {
+            return x;
+        }
+    }
     let ui = x.to_bits();
     let e = ((ui >> 52) & 0x7ff) as i32;