From f265e82722cdb38a4c3997c2763c41e7818d3138 Mon Sep 17 00:00:00 2001
From: Jan Pfeifer <pfeifer@gmail.com>
Date: Tue, 27 Aug 2024 12:07:03 +0200
Subject: [PATCH 1/4] Removed some panics and dependency to
 github.com/gomlx/exceptions from dtypes.

---
 dtypes/dtypes.go      | 40 +++++++++++++++++++++++++++++-----------
 dtypes/dtypes_test.go | 23 +++++++++++++++++++++++
 2 files changed, 52 insertions(+), 11 deletions(-)
 create mode 100644 dtypes/dtypes_test.go

diff --git a/dtypes/dtypes.go b/dtypes/dtypes.go
index 2464621..c65c044 100644
--- a/dtypes/dtypes.go
+++ b/dtypes/dtypes.go
@@ -1,14 +1,30 @@
 package dtypes
 
 import (
-	"github.com/gomlx/exceptions"
 	"github.com/gomlx/gopjrt/dtypes/bfloat16"
+	"github.com/pkg/errors"
 	"github.com/x448/float16"
 	"math"
 	"reflect"
 	"strconv"
 )
 
+// panicf panics with formatted description.
+//
+// It is only used for "bugs in the code" -- when parameters don't follow the specifications.
+// In principle it should never happen -- the same way nil-pointer panics should never happen.
+func panicf(format string, args ...any) {
+	panic(errors.Errorf(format, args...))
+}
+
+func init() {
+	// Only works for 32 and 64 bits platforms.
+	// TODO: find some compile-time check.
+	if strconv.IntSize != 32 && strconv.IntSize != 64 {
+		panicf("cannot use int of %d bits with gopjrt -- only platforms with int32 or int64 are supported", strconv.IntSize)
+	}
+}
+
 // Generate automatic C-to-Go boilerplate code for pjrt_c_api.h.
 //go:generate go run ../cmd/dtypes_codegen
 
@@ -31,7 +47,7 @@ func FromGenericsType[T Supported]() DType {
 		case 64:
 			return Int64
 		default:
-			exceptions.Panicf("Cannot use int of %d bits with gopjrt -- try using int32 or int64", strconv.IntSize)
+			panicf("Cannot use int of %d bits with gopjrt -- try using int32 or int64", strconv.IntSize)
 		}
 	case int64:
 		return Int64
@@ -75,7 +91,7 @@ func FromGoType(t reflect.Type) DType {
 		case 64:
 			return Int64
 		default:
-			exceptions.Panicf("cannot use int of %d bits with GoMLX -- try using int32 or int64", strconv.IntSize)
+			panicf("cannot use int of %d bits with GoMLX -- try using int32 or int64", strconv.IntSize)
 		}
 	case reflect.Int64:
 		return Int64
@@ -177,8 +193,10 @@ func (dtype DType) GoType() reflect.Type {
 		return reflect.TypeOf(complex128(0))
 
 	default:
-		exceptions.Panicf("unknown dtype %q (%d) in DType.GoType", dtype, dtype)
-		panic(nil) // Quiet lint warning.
+		// This should never happen, except if someone entered an invalid DType number beyond the values
+		// defined.
+		panicf("unknown dtype %q (%d) in DType.GoType", dtype, dtype)
+		panic(nil)
 	}
 }
 
@@ -224,9 +242,9 @@ func (dtype DType) LowestValue() any {
 		return bfloat16.Inf(-1)
 
 	default:
-		exceptions.Panicf("LowestValue for dtype %s not defined", dtype)
+		// For invalid dtypes (like complex numbers), return zero.
+		return reflect.New(dtype.GoType()).Elem().Interface()
 	}
-	return 0 // Never reaches here.
 }
 
 // HighestValue for dtype converted to the corresponding Go type.
@@ -265,9 +283,9 @@ func (dtype DType) HighestValue() any {
 		return bfloat16.Inf(1)
 
 	default:
-		exceptions.Panicf("LowestValue for dtype %s not defined", dtype)
+		// For invalid dtypes (like complex numbers), return zero.
+		return reflect.New(dtype.GoType()).Elem().Interface()
 	}
-	return 0 // Never reaches here.
 }
 
 // SmallestNonZeroValueForDType is the smallest non-zero value dtypes.
@@ -307,8 +325,8 @@ func (dtype DType) SmallestNonZeroValueForDType() any {
 		return bfloat16.SmallestNonzero // 1p-24, see discussion in https://github.com/x448/float16/pull/46
 
 	default:
-		exceptions.Panicf("SmallestNonZeroValueForDType not defined for dtype %s", dtype)
-		panic(nil) // Removes lint warning.
+		// For invalid dtypes (like complex numbers), return zero.
+		return reflect.New(dtype.GoType()).Elem().Interface()
 	}
 }
 
diff --git a/dtypes/dtypes_test.go b/dtypes/dtypes_test.go
new file mode 100644
index 0000000..fec8990
--- /dev/null
+++ b/dtypes/dtypes_test.go
@@ -0,0 +1,23 @@
+package dtypes
+
+import (
+	"github.com/gomlx/gopjrt/dtypes/bfloat16"
+	"github.com/stretchr/testify/require"
+	"github.com/x448/float16"
+	"math"
+	"testing"
+)
+
+func TestDType_HighestLowestSmallestValues(t *testing.T) {
+	require.True(t, math.IsInf(Float64.HighestValue().(float64), 1))
+	require.True(t, math.IsInf(float64(Float32.LowestValue().(float32)), -1))
+	_, ok := Float16.SmallestNonZeroValueForDType().(float16.Float16)
+	require.True(t, ok)
+	_, ok = BFloat16.SmallestNonZeroValueForDType().(bfloat16.BFloat16)
+	require.True(t, ok)
+
+	// Complex numbers don't define Highest of Lowest, and instead return 0
+	require.Equal(t, complex64(0), Complex64.HighestValue().(complex64))
+	require.Equal(t, complex128(0), Complex128.LowestValue().(complex128))
+	require.Equal(t, complex64(0), Complex64.SmallestNonZeroValueForDType().(complex64))
+}

From 9d49024d2a7ff510519ac6bd28b91ee8c161fc62 Mon Sep 17 00:00:00 2001
From: Jan Pfeifer <pfeifer@gmail.com>
Date: Tue, 27 Aug 2024 12:07:36 +0200
Subject: [PATCH 2/4] Improve to documentation.

---
 xlabuilder/shape.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xlabuilder/shape.go b/xlabuilder/shape.go
index b0bc04f..dbda736 100644
--- a/xlabuilder/shape.go
+++ b/xlabuilder/shape.go
@@ -33,7 +33,8 @@ type Shape struct {
 }
 
 // MakeShape filled with the values given.
-// It doesn't work for tuple shapes.
+//
+// The dimensions must be >= 1, and it doesn't work for tuple shapes.
 func MakeShape(dtype dtypes.DType, dimensions ...int) Shape {
 	s := Shape{Dimensions: slices.Clone(dimensions), DType: dtype}
 	for _, dim := range dimensions {

From 3b0298274cab9d379e0460b403bd06378fa5be0f Mon Sep 17 00:00:00 2001
From: Jan Pfeifer <pfeifer@gmail.com>
Date: Tue, 27 Aug 2024 12:19:55 +0200
Subject: [PATCH 3/4] Removed dependency on github.com/gomlx/exceptions.

---
 cmd/dtypes_codegen/enums.go    | 12 ++++++++++--
 cmd/xlabuilder_codegen/main.go | 12 ++++++++++--
 docs/coverage.out              | 31 ++++++++++++++++---------------
 dtypes/dtypes.go               |  2 +-
 go.mod                         |  2 --
 go.sum                         |  4 ----
 pjrt/loadedexecutables.go      |  3 +--
 pjrt/pjrt.go                   | 10 ++++++++++
 xlabuilder/literal.go          |  9 ++-------
 xlabuilder/shape.go            |  3 +--
 xlabuilder/special_ops.go      |  5 ++---
 xlabuilder/xlabuilder.go       | 11 +++++++++--
 xlabuilder/xlacomputation.go   |  5 ++---
 13 files changed, 64 insertions(+), 45 deletions(-)

diff --git a/cmd/dtypes_codegen/enums.go b/cmd/dtypes_codegen/enums.go
index cd7fb96..4333439 100644
--- a/cmd/dtypes_codegen/enums.go
+++ b/cmd/dtypes_codegen/enums.go
@@ -2,9 +2,9 @@ package main
 
 import (
 	"fmt"
-	"github.com/gomlx/exceptions"
 	"github.com/gomlx/gopjrt/protos/xla_data"
 	"github.com/janpfeifer/must"
+	"github.com/pkg/errors"
 	"os"
 	"os/exec"
 	"regexp"
@@ -17,6 +17,14 @@ const (
 	DTypeEnumGoFileName = "gen_dtype_enum.go"
 )
 
+// panicf panics with formatted description.
+//
+// It is only used for "bugs in the code" -- when parameters don't follow the specifications.
+// In principle, it should never happen -- the same way nil-pointer panics should never happen.
+func panicf(format string, args ...any) {
+	panic(errors.Errorf(format, args...))
+}
+
 var aliases = map[string]string{
 	"INVALID": "InvalidDType",
 	"PRED":    "Bool",
@@ -121,7 +129,7 @@ func generateEnums(contents string) {
 	var enumV *enumValue
 	matches := reEnums.FindStringSubmatch(contents)
 	if len(matches) == 0 {
-		exceptions.Panicf("failed to match PJRT_Buffer_Types enum from pjrt_c_api.h")
+		panicf("failed to match PJRT_Buffer_Types enum from pjrt_c_api.h")
 	}
 	for _, line := range strings.Split(matches[2], "\n") {
 		if line == "" {
diff --git a/cmd/xlabuilder_codegen/main.go b/cmd/xlabuilder_codegen/main.go
index 7b3194c..31b1e45 100644
--- a/cmd/xlabuilder_codegen/main.go
+++ b/cmd/xlabuilder_codegen/main.go
@@ -4,8 +4,8 @@ package main
 import (
 	"bufio"
 	"fmt"
-	"github.com/gomlx/exceptions"
 	"github.com/janpfeifer/must"
+	"github.com/pkg/errors"
 	"os"
 	"strings"
 )
@@ -17,6 +17,14 @@ type OpInfo struct {
 	Comments   []string
 }
 
+// panicf panics with formatted description.
+//
+// It is only used for "bugs in the code" -- when parameters don't follow the specifications.
+// In principle, it should never happen -- the same way nil-pointer panics should never happen.
+func panicf(format string, args ...any) {
+	panic(errors.Errorf(format, args...))
+}
+
 func main() {
 	// Read op_types.xt
 	opsInfo := make([]OpInfo, 0, 200)
@@ -40,7 +48,7 @@ func main() {
 		}
 		parts := strings.Split(line, ":")
 		if len(parts) != 2 {
-			exceptions.Panicf("Invalid op definition in %q:%d : %q", OpTypesFileName, lineNum, line)
+			panicf("Invalid op definition in %q:%d : %q", OpTypesFileName, lineNum, line)
 		}
 		if len(comments) == 0 {
 			comments = append(comments, fmt.Sprintf("%s returns the Op that represents the output of the corresponding operation.", parts[0]))
diff --git a/docs/coverage.out b/docs/coverage.out
index b75db28..caf395c 100644
--- a/docs/coverage.out
+++ b/docs/coverage.out
@@ -90,24 +90,25 @@ github.com/gomlx/gopjrt/pjrt/gen_chelper.go:62:		cMallocArrayAndSet			100.0%
 github.com/gomlx/gopjrt/pjrt/gen_chelper.go:73:		cDataToSlice				100.0%
 github.com/gomlx/gopjrt/pjrt/gen_chelper.go:79:		cCharArray				100.0%
 github.com/gomlx/gopjrt/pjrt/gen_chelper.go:86:		cStrFree				0.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:37:	newLoadedExecutable			64.7%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:67:	Destroy					91.7%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:86:	destroyOrLog				66.7%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:94:	getExecutable				80.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:122:	Execute					100.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:152:	OnDevices				0.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:187:	OnDevicesByNum				0.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:211:	DonateAll				0.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:220:	DonateNone				100.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:234:	Donate					0.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:245:	SetDonate				0.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:262:	Done					88.6%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:319:	allocatePerDeviceBufferList		88.9%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:339:	freePerDeviceBufferList			100.0%
-github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:348:	gatherPerDeviceBufferList		100.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:36:	newLoadedExecutable			64.7%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:66:	Destroy					91.7%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:85:	destroyOrLog				66.7%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:93:	getExecutable				80.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:121:	Execute					100.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:151:	OnDevices				0.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:186:	OnDevicesByNum				0.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:210:	DonateAll				0.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:219:	DonateNone				100.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:233:	Donate					0.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:244:	SetDonate				0.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:261:	Done					88.6%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:318:	allocatePerDeviceBufferList		88.9%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:338:	freePerDeviceBufferList			100.0%
+github.com/gomlx/gopjrt/pjrt/loadedexecutables.go:347:	gatherPerDeviceBufferList		100.0%
 github.com/gomlx/gopjrt/pjrt/namedvalues.go:20:		pjrtNamedValuesToMap			25.0%
 github.com/gomlx/gopjrt/pjrt/namedvalues.go:50:		mallocArrayPJRT_NamedValue		6.7%
 github.com/gomlx/gopjrt/pjrt/namedvalues.go:101:	destroyPJRT_NamedValue			0.0%
+github.com/gomlx/gopjrt/pjrt/pjrt.go:17:		panicf					0.0%
 github.com/gomlx/gopjrt/pjrt/plugins.go:32:		pjrtPluginInitialize			100.0%
 github.com/gomlx/gopjrt/pjrt/plugins.go:40:		pjrtPluginAttributes			87.5%
 github.com/gomlx/gopjrt/pjrt/plugins.go:54:		newPlugin				75.0%
diff --git a/dtypes/dtypes.go b/dtypes/dtypes.go
index c65c044..8f5f5b2 100644
--- a/dtypes/dtypes.go
+++ b/dtypes/dtypes.go
@@ -12,7 +12,7 @@ import (
 // panicf panics with formatted description.
 //
 // It is only used for "bugs in the code" -- when parameters don't follow the specifications.
-// In principle it should never happen -- the same way nil-pointer panics should never happen.
+// In principle, it should never happen -- the same way nil-pointer panics should never happen.
 func panicf(format string, args ...any) {
 	panic(errors.Errorf(format, args...))
 }
diff --git a/go.mod b/go.mod
index 59c97c8..a73cea9 100644
--- a/go.mod
+++ b/go.mod
@@ -3,9 +3,7 @@ module github.com/gomlx/gopjrt
 go 1.23
 
 require (
-	github.com/chenxingqiang/go-floatx v0.0.0-20240103165049-2f5e300cb3c3
 	github.com/chewxy/math32 v1.10.1
-	github.com/gomlx/exceptions v0.0.3
 	github.com/janpfeifer/gonb v0.10.1
 	github.com/janpfeifer/must v0.0.2
 	github.com/pkg/errors v0.9.1
diff --git a/go.sum b/go.sum
index 6650806..1d7caf0 100644
--- a/go.sum
+++ b/go.sum
@@ -1,5 +1,3 @@
-github.com/chenxingqiang/go-floatx v0.0.0-20240103165049-2f5e300cb3c3 h1:2m11dpwbI3ccPgDbAbJ8X6fonuzsi54n70duaraoLn8=
-github.com/chenxingqiang/go-floatx v0.0.0-20240103165049-2f5e300cb3c3/go.mod h1:7v935pWqAb/hfUDQyVXq8eXUoXWa7Mub1xEuRbtTFWE=
 github.com/chewxy/math32 v1.10.1 h1:LFpeY0SLJXeaiej/eIp2L40VYfscTvKh/FSEZ68uMkU=
 github.com/chewxy/math32 v1.10.1/go.mod h1:dOB2rcuFrCn6UHrze36WSLVPKtzPMRAQvBvUwkSsLqs=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
@@ -8,8 +6,6 @@ github.com/go-logr/logr v1.4.1 h1:pKouT5E8xu9zeFC39JXRDukb6JFQPXM5p5I91188VAQ=
 github.com/go-logr/logr v1.4.1/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
 github.com/gofrs/uuid v4.4.0+incompatible h1:3qXRTX8/NbyulANqlc0lchS1gqAVxRgsuW1YrTJupqA=
 github.com/gofrs/uuid v4.4.0+incompatible/go.mod h1:b2aQJv3Z4Fp6yNu3cdSllBxTCLRxnplIgP/c0N/04lM=
-github.com/gomlx/exceptions v0.0.3 h1:HKnTgEjj4jlmhr8zVFkTP9qmV1ey7ypYYosQ8GzXWuM=
-github.com/gomlx/exceptions v0.0.3/go.mod h1:uHL0TQwJ0xaV2/snJOJV6hSE4yRmhhfymuYgNredGxU=
 github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
 github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/janpfeifer/gonb v0.10.1 h1:yk29LAN5EF0OMKdnXd6xWTmlI/Tedajk7ssVu/1eBis=
diff --git a/pjrt/loadedexecutables.go b/pjrt/loadedexecutables.go
index fa52bb9..6dcafe6 100644
--- a/pjrt/loadedexecutables.go
+++ b/pjrt/loadedexecutables.go
@@ -7,7 +7,6 @@ package pjrt
 */
 import "C"
 import (
-	"github.com/gomlx/exceptions"
 	"github.com/pkg/errors"
 	"k8s.io/klog/v2"
 	"runtime"
@@ -327,7 +326,7 @@ func allocatePerDeviceBufferList(numDevices int, buffers []*Buffer) ***C.PJRT_Bu
 			}
 			if buffers[idxBuffer].cBuffer == nil {
 				// Buffer given, but it's cBuffer is nil -> probably it has already been destroyed.
-				exceptions.Panicf("buffers[%d].cBuffer is nil, has it already been destroyed!?", idxBuffer)
+				panicf("buffers[%d].cBuffer is nil, has it already been destroyed!?", idxBuffer)
 			}
 			return buffers[idxBuffer].cBuffer
 		})
diff --git a/pjrt/pjrt.go b/pjrt/pjrt.go
index fe842c6..7280cc5 100644
--- a/pjrt/pjrt.go
+++ b/pjrt/pjrt.go
@@ -1,9 +1,19 @@
 // Package pjrt implements a Go wrapper for the PJRT_C_API.
 package pjrt
 
+import "github.com/pkg/errors"
+
 // Generate automatic C-to-Go boilerplate code for pjrt_c_api.h.
 //go:generate go run ../cmd/pjrt_codegen
 
 // Since CGO C types cannot cross boundaries of a package (see issue https://github.com/golang/go/issues/13467)
 // We make a copy of chelper.go for every sub-directory that needs it.
 //go:generate go run ../cmd/copy_go_code --original=chelper.go
+
+// panicf panics with formatted description.
+//
+// It is only used for "bugs in the code" -- when parameters don't follow the specifications.
+// In principle, it should never happen -- the same way nil-pointer panics should never happen.
+func panicf(format string, args ...any) {
+	panic(errors.Errorf(format, args...))
+}
diff --git a/xlabuilder/literal.go b/xlabuilder/literal.go
index 5b47e81..b1b6782 100644
--- a/xlabuilder/literal.go
+++ b/xlabuilder/literal.go
@@ -5,7 +5,6 @@ package xlabuilder
 */
 import "C"
 import (
-	"github.com/gomlx/exceptions"
 	"github.com/gomlx/gopjrt/dtypes"
 	"github.com/gomlx/gopjrt/dtypes/bfloat16"
 	"github.com/pkg/errors"
@@ -98,12 +97,8 @@ func NewScalarLiteralFromFloat64(value float64, dtype dtypes.DType) (*Literal, e
 		return NewScalarLiteral(bfloat16.FromFloat32(float32(value))), nil
 	default:
 		var convertedValue reflect.Value
-		panicMsg := exceptions.Try(func() {
-			convertedValue = reflect.ValueOf(value).Convert(dtype.GoType())
-		})
-		if panicMsg != nil {
-			return nil, errors.Errorf("failed to convert %g to dtype %s: %v", value, dtype, panicMsg)
-		}
+		convertedValue = reflect.ValueOf(value)
+		convertedValue = convertedValue.Convert(dtype.GoType())
 		l, err := NewLiteralFromShape(MakeShape(dtype))
 		if err != nil {
 			return nil, err
diff --git a/xlabuilder/shape.go b/xlabuilder/shape.go
index dbda736..473b1c7 100644
--- a/xlabuilder/shape.go
+++ b/xlabuilder/shape.go
@@ -6,7 +6,6 @@ package xlabuilder
 import "C"
 import (
 	"fmt"
-	"github.com/gomlx/exceptions"
 	"github.com/gomlx/gopjrt/dtypes"
 	"github.com/gomlx/gopjrt/protos/xla_data"
 	"github.com/pkg/errors"
@@ -39,7 +38,7 @@ func MakeShape(dtype dtypes.DType, dimensions ...int) Shape {
 	s := Shape{Dimensions: slices.Clone(dimensions), DType: dtype}
 	for _, dim := range dimensions {
 		if dim <= 0 {
-			exceptions.Panicf("shapes.Make(%+v): cannot create a shape with an axis with dimension <= 0", s)
+			panicf("shapes.Make(%+v): cannot create a shape with an axis with dimension <= 0", s)
 		}
 	}
 	return s
diff --git a/xlabuilder/special_ops.go b/xlabuilder/special_ops.go
index b5b9603..62d230d 100644
--- a/xlabuilder/special_ops.go
+++ b/xlabuilder/special_ops.go
@@ -2,7 +2,6 @@ package xlabuilder
 
 import (
 	"fmt"
-	"github.com/gomlx/exceptions"
 	"github.com/gomlx/gopjrt/dtypes"
 	"github.com/gomlx/gopjrt/protos/xla_data"
 	"github.com/pkg/errors"
@@ -119,7 +118,7 @@ func DecodeIota(op *Op) (shape Shape, iotaAxis int) {
 func Identity(input *Op) *Op {
 	builder := input.builder
 	if builder.IsNil() {
-		exceptions.Panicf("trying to access XlaBuilder that is nil or already destroyed")
+		panicf("trying to access XlaBuilder that is nil or already destroyed")
 	}
 	op := newOp(IdentityOp)
 	op.OpInputs = []*Op{input}
@@ -455,7 +454,7 @@ func Slice(x *Op, starts, limits, strides []int) (*Op, error) {
 func DecodeSlice(op *Op) (starts, limits, strides []int) {
 	rank := op.OpInputs[0].Shape.Rank()
 	if len(op.IntsArg) != 3*rank {
-		exceptions.Panicf("DecodeSlice() has input of rank %d, but arguments don't have 3*%d elements, instead got %d",
+		panicf("DecodeSlice() has input of rank %d, but arguments don't have 3*%d elements, instead got %d -- probably the op as not a SliceOp?",
 			rank, 3*rank, len(op.IntsArg))
 	}
 	starts = op.IntsArg[0:rank]
diff --git a/xlabuilder/xlabuilder.go b/xlabuilder/xlabuilder.go
index ecaf3f0..2700309 100644
--- a/xlabuilder/xlabuilder.go
+++ b/xlabuilder/xlabuilder.go
@@ -6,7 +6,6 @@ package xlabuilder
 */
 import "C"
 import (
-	"github.com/gomlx/exceptions"
 	"github.com/pkg/errors"
 	"runtime"
 	"unsafe"
@@ -18,6 +17,14 @@ import (
 // We make a copy of chelper.go for every sub-directory that needs it.
 //go:generate go run ../cmd/copy_go_code --original=chelper.go
 
+// panicf panics with formatted description.
+//
+// It is only used for "bugs in the code" -- when parameters don't follow the specifications.
+// In principle, it should never happen -- the same way nil-pointer panics should never happen.
+func panicf(format string, args ...any) {
+	panic(errors.Errorf(format, args...))
+}
+
 // XlaBuilder is used to create "computations" (XlaComputation), that are like "StableHLO" functions.
 //
 // In turn XlaComputation can be exported to a serialized `HloModuleProto` (a binary blob) and used by a PJRT plugin
@@ -163,7 +170,7 @@ func (b *XlaBuilder) Build(outputOp *Op) (*XlaComputation, error) {
 // It takes as input the computationName that is going to be built with it.
 func (b *XlaBuilder) CreateSubBuilder(computationName string) *XlaBuilder {
 	if b.IsNil() {
-		exceptions.Panicf("trying to access XlaBuilder that is nil or already destroyed")
+		panicf("trying to access XlaBuilder that is nil or already destroyed")
 	}
 	cName := C.CString(computationName)
 	defer cFree(cName)
diff --git a/xlabuilder/xlacomputation.go b/xlabuilder/xlacomputation.go
index 87de081..7e996d2 100644
--- a/xlabuilder/xlacomputation.go
+++ b/xlabuilder/xlacomputation.go
@@ -6,7 +6,6 @@ package xlabuilder
 */
 import "C"
 import (
-	"github.com/gomlx/exceptions"
 	"github.com/gomlx/gopjrt/cbuffer"
 	"runtime"
 	"unsafe"
@@ -69,7 +68,7 @@ func (comp *XlaComputation) Name() string {
 // See XlaComputation documentation on how to pretty-print the computation as text HLO.
 func (comp *XlaComputation) SerializedHLO() *cbuffer.CBuffer {
 	if comp.IsNil() {
-		exceptions.Panicf("XlaComputation is nil, maybe it has already been destroyed?")
+		panicf("XlaComputation is nil, maybe it has already been destroyed?")
 	}
 	defer runtime.KeepAlive(comp)
 	if comp == nil || comp.cXlaComputation == nil {
@@ -86,7 +85,7 @@ func (comp *XlaComputation) SerializedHLO() *cbuffer.CBuffer {
 // Alternatively, see XlaComputation documentation on how to pretty-print the computation as text HLO.
 func (comp *XlaComputation) TextHLO() string {
 	if comp.IsNil() {
-		exceptions.Panicf("XlaComputation is nil, maybe it has already been destroyed?")
+		panicf("XlaComputation is nil, maybe it has already been destroyed?")
 	}
 	defer runtime.KeepAlive(comp)
 	if comp == nil || comp.cXlaComputation == nil {

From 3b63a31a0ab51ae167d6015ce9e5c2d9c8196ef9 Mon Sep 17 00:00:00 2001
From: Jan Pfeifer <pfeifer@gmail.com>
Date: Tue, 27 Aug 2024 12:22:04 +0200
Subject: [PATCH 4/4] Updated CHANGELOG.

---
 docs/CHANGELOG.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index b16c74b..944f2eb 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -1,6 +1,7 @@
-# Nexxt
+# v0.3.1
 
 * Fixed +/-Inf for bfloat16.
+* Removed dependencies on "github.com/gomlx/exceptions".
 
 # v0.3.0 Some of the API now returns errors instead of panic