variable-precision float operations behave non-deterministically

Author: RalfJung

library/std/src/f32.rs

@@ -373,7 +373,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -395,7 +396,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -446,7 +448,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -472,7 +475,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -496,7 +500,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -526,7 +531,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -550,7 +556,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -574,7 +581,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -601,7 +609,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `fdimf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -639,7 +648,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `cbrtf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -668,7 +678,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `hypotf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -695,7 +706,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -718,7 +730,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -741,7 +754,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `tanf` from libc on Unix and
     /// Windows. Note that this might change in the future.
     ///
@@ -767,7 +781,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `asinf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -796,7 +811,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `acosf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -824,7 +840,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `atanf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -856,7 +873,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `atan2f` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -892,7 +910,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `(f32::sin(x),
     /// f32::cos(x))`. Note that this might change in the future.
     ///
@@ -921,7 +940,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `expm1f` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -949,7 +969,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `log1pf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -977,7 +998,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `sinhf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -1006,7 +1028,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `coshf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -1035,7 +1058,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `tanhf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -1064,7 +1088,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -1091,7 +1116,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -1120,7 +1146,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     ///
     /// # Examples
     ///
@@ -1145,7 +1172,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `tgammaf` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///
@@ -1173,7 +1201,8 @@ impl f32 {
     ///
     /// # Platform-specific precision
     ///
-    /// The precision of this function varies by platform and Rust version.
+    /// The precision of this function is non-deterministic. This means it varies by platform, Rust version, and
+    /// even can even differ within the same execution from one invocation to the next.
     /// This function currently corresponds to the `lgamma_r` from libc on Unix
     /// and Windows. Note that this might change in the future.
     ///