diff --git a/.github/workflows/coroutine.yml b/.github/workflows/coroutine.yml
index 5193f80..97b443d 100644
--- a/.github/workflows/coroutine.yml
+++ b/.github/workflows/coroutine.yml
@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        llvm: [19, 21, 22]
+        llvm: [19, 20, 21, 22]
     steps:
       - uses: actions/checkout@v4
 
diff --git a/.github/workflows/go.yml b/.github/workflows/go.yml
index 8df976c..66f886c 100644
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -20,20 +20,15 @@ jobs:
     strategy:
       matrix:
         llvm: [14, 15, 16, 17, 18, 19, 20, 21, 22]
-        go-version: [1.18.x, 1.21.x, 1.22.x]
     steps:
       - name: Checkout
         uses: actions/checkout@v4
       - name: Set up Go
         uses: actions/setup-go@v5
         with:
-          go-version: ${{ matrix.go-version }}
-      #- name: Update Homebrew
-      #  if: matrix.llvm == 17 # needed as long as LLVM 17 is still fresh
-      #  run: brew update
+          go-version: '1.22'
       # Optional step when a LLVM version is very new.
       - name: Update Homebrew
-        if: matrix.llvm == 22
         run: brew update
       - name: Install LLVM
         run: HOMEBREW_NO_AUTO_UPDATE=1 brew install llvm@${{ matrix.llvm }}
@@ -69,3 +64,26 @@ jobs:
         if: matrix.llvm == 19
         run:
           go test -v
+  test-linux-fedora:
+    # Fedora uses different paths than other systems, so testing it separately.
+    runs-on: ubuntu-24.04
+    strategy:
+      matrix:
+        llvm: [19, 20, 21]
+    container: fedora:43
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install dependencies (default LLVM)
+        if: matrix.llvm == 21
+        run: dnf install --assumeyes g++ golang llvm-devel
+      - name: Install dependencies (older LLVM)
+        if: matrix.llvm != 21
+        run: dnf install --assumeyes g++ golang llvm${{ matrix.llvm }}-devel
+      - name: Test LLVM ${{ matrix.llvm }}
+        run:
+          go test -v -tags=llvm${{ matrix.llvm }}
+      - name: Test default LLVM
+        if: matrix.llvm == 19
+        run:
+          go test -v
diff --git a/captures_test.go b/captures_test.go
new file mode 100644
index 0000000..5021b9a
--- /dev/null
+++ b/captures_test.go
@@ -0,0 +1,48 @@
+package llvm
+
+import (
+	"strconv"
+	"strings"
+	"testing"
+)
+
+// TestCapturesAttribute checks that the 'captures' parameter attribute
+// (which replaced the boolean 'nocapture' enum attribute starting with
+// LLVM 21) round-trips through the generic enum-attribute API, and that a
+// value of 0 corresponds to CaptureInfo::none(), i.e. captures(none).
+func TestCapturesAttribute(t *testing.T) {
+	majorVersion, _ := strconv.Atoi(strings.SplitN(Version, ".", 2)[0])
+	if majorVersion < 21 {
+		t.Skip("not llvm 21")
+	}
+
+	ctx := NewContext()
+	defer ctx.Dispose()
+	mod := ctx.NewModule("")
+	defer mod.Dispose()
+
+	ptrType := PointerType(ctx.Int8Type(), 0)
+	ftyp := FunctionType(ctx.VoidType(), []Type{ptrType}, false)
+	fn := AddFunction(mod, "foo", ftyp)
+
+	kind := AttributeKindID("captures")
+	if kind == 0 {
+		t.Fatal("captures kind id not found")
+	}
+
+	attr := ctx.CreateEnumAttribute(kind, 0)
+	fn.AddAttributeAtIndex(1, attr)
+
+	got := fn.GetEnumAttributeAtIndex(1, kind)
+	if got.IsNil() {
+		t.Fatal("expected captures attribute on param 1, got nil")
+	}
+	if val := got.GetEnumValue(); val != 0 {
+		t.Errorf("expected captures value 0 (none), got %d", val)
+	}
+
+	text := mod.String()
+	if !strings.Contains(text, "captures(none)") {
+		t.Errorf("expected 'captures(none)' in output, got:\n%s", text)
+	}
+}
diff --git a/ir.go b/ir.go
index 573c531..99a0921 100644
--- a/ir.go
+++ b/ir.go
@@ -828,6 +828,18 @@ func (v Value) Operand(i int) (rv Value)   { rv.C = C.LLVMGetOperand(v.C, C.unsi
 func (v Value) SetOperand(i int, op Value) { C.LLVMSetOperand(v.C, C.unsigned(i), op.C) }
 func (v Value) OperandsCount() int         { return int(C.LLVMGetNumOperands(v.C)) }
 
+// Operations on terminator instructions (br, switch, etc). Unlike operands,
+// the number and meaning of successors has been stable across LLVM versions,
+// making these a safe, version-independent way to enumerate the destination
+// blocks of a switch instruction: successor 0 is the default destination,
+// and successors 1..N-1 correspond to case 0..N-2 (see GetSwitchCaseValue for
+// the matching case value).
+func (v Value) SuccessorsCount() int { return int(C.LLVMGetNumSuccessors(v.C)) }
+func (v Value) Successor(i int) (bb BasicBlock) {
+	bb.C = C.LLVMGetSuccessor(v.C, C.unsigned(i))
+	return
+}
+
 // Operations on constants of any type
 // ConstTokenNone returns the empty token constant owned by c.
 func (c Context) ConstTokenNone() (v Value) {
diff --git a/llvm_config_llvm19.go b/llvm_config_llvm19.go
index 71cd53c..fea3f0b 100644
--- a/llvm_config_llvm19.go
+++ b/llvm_config_llvm19.go
@@ -1,4 +1,5 @@
 //go:build !byollvm && !llvm14 && !llvm15 && !llvm16 && !llvm17 && !llvm18 && !llvm20 && !llvm21 && !llvm22
+// +build !byollvm,!llvm14,!llvm15,!llvm16,!llvm17,!llvm18,!llvm20,!llvm21,!llvm22
 
 package llvm
 
@@ -11,9 +12,9 @@ package llvm
 // #cgo freebsd      CPPFLAGS: -I/usr/local/llvm19/include -I/usr/local/llvm19/include/llvm-c -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
 // #cgo freebsd      CXXFLAGS: -std=c++17
 // #cgo freebsd      LDFLAGS: -L/usr/local/llvm19/lib -lLLVM
-// #cgo linux        CPPFLAGS: -I/usr/include/llvm-19 -I/usr/include/llvm-c-19 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
+// #cgo linux        CPPFLAGS: -I/usr/include/llvm-19 -I/usr/include/llvm-c-19 -I/usr/lib64/llvm19/include -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
 // #cgo linux        CXXFLAGS: -std=c++17
-// #cgo linux        LDFLAGS: -L/usr/lib/llvm-19/lib -lLLVM-19
+// #cgo linux        LDFLAGS: -L/usr/lib/llvm-19/lib -L/usr/lib64/llvm19/lib -lLLVM-19
 import "C"
 
 type run_build_sh int
diff --git a/llvm_config_llvm20.go b/llvm_config_llvm20.go
index 090bdd6..d67281a 100644
--- a/llvm_config_llvm20.go
+++ b/llvm_config_llvm20.go
@@ -1,4 +1,5 @@
 //go:build !byollvm && llvm20
+// +build !byollvm,llvm20
 
 package llvm
 
@@ -11,9 +12,9 @@ package llvm
 // #cgo freebsd      CPPFLAGS: -I/usr/local/llvm20/include -I/usr/local/llvm20/include/llvm-c -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
 // #cgo freebsd      CXXFLAGS: -std=c++17
 // #cgo freebsd      LDFLAGS: -L/usr/local/llvm20/lib -lLLVM
-// #cgo linux        CPPFLAGS: -I/usr/include/llvm-20 -I/usr/include/llvm-c-20 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
+// #cgo linux        CPPFLAGS: -I/usr/include/llvm-20 -I/usr/include/llvm-c-20 -I/usr/lib64/llvm20/include -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
 // #cgo linux        CXXFLAGS: -std=c++17
-// #cgo linux        LDFLAGS: -L/usr/lib/llvm-20/lib -lLLVM-20
+// #cgo linux        LDFLAGS: -L/usr/lib/llvm-20/lib -L/usr/lib64/llvm20/lib64 -lLLVM-20
 import "C"
 
 type run_build_sh int
diff --git a/switch_llvm22.go b/switch_llvm22.go
new file mode 100644
index 0000000..0c70b08
--- /dev/null
+++ b/switch_llvm22.go
@@ -0,0 +1,21 @@
+//go:build llvm22
+
+package llvm
+
+/*
+#include "llvm-c/Core.h"
+*/
+import "C"
+
+// GetSwitchCaseValue obtains the case value for a successor of a switch
+// instruction. i corresponds to the successor index; the first successor (0)
+// is the default destination, so i must be greater than zero.
+//
+// LLVM 22 stopped exposing switch case values as regular instruction
+// operands (only the condition and destination-block operands remain), so
+// this is implemented via the new LLVMGetSwitchCaseValue C API added in the
+// same release.
+func (v Value) GetSwitchCaseValue(i int) (rv Value) {
+	rv.C = C.LLVMGetSwitchCaseValue(v.C, C.unsigned(i))
+	return
+}
diff --git a/switch_pre22.go b/switch_pre22.go
new file mode 100644
index 0000000..cfa381c
--- /dev/null
+++ b/switch_pre22.go
@@ -0,0 +1,15 @@
+//go:build !llvm22
+
+package llvm
+
+// GetSwitchCaseValue obtains the case value for a successor of a switch
+// instruction. i corresponds to the successor index; the first successor (0)
+// is the default destination, so i must be greater than zero.
+//
+// Before LLVM 22, switch case values were stored as regular instruction
+// operands (alternating with their destination blocks, after the leading
+// condition/default-destination pair), so this is implemented via Operand
+// access instead of the LLVM 22+-only LLVMGetSwitchCaseValue.
+func (v Value) GetSwitchCaseValue(i int) Value {
+	return v.Operand(2 * i)
+}
diff --git a/switch_test.go b/switch_test.go
new file mode 100644
index 0000000..8cd9c8c
--- /dev/null
+++ b/switch_test.go
@@ -0,0 +1,79 @@
+package llvm
+
+import (
+	"os"
+	"testing"
+)
+
+// TestSwitchCaseValue checks that GetSwitchCaseValue/SuccessorsCount/Successor
+// correctly read a switch instruction's cases across LLVM versions. LLVM 22
+// stopped exposing case values as regular instruction operands (only the
+// condition and destination-block operands remain), instead requiring the
+// new LLVMGetSwitchCaseValue API; code that assumed the old operand layout
+// silently reads a destination block where it expects a case value.
+func TestSwitchCaseValue(t *testing.T) {
+	src := `
+define void @foo(i64 %callback) {
+entry:
+  switch i64 %callback, label %default [
+    i64 0, label %case0
+    i64 5, label %case1
+  ]
+default:
+  ret void
+case0:
+  ret void
+case1:
+  ret void
+}
+`
+	f, err := os.CreateTemp("", "switchcase-*.ll")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+	defer os.Remove(f.Name())
+	if _, err := f.WriteString(src); err != nil {
+		t.Fatal(err)
+	}
+	if err := f.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	ctx := NewContext()
+	defer ctx.Dispose()
+
+	buf, err := NewMemoryBufferFromFile(f.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	m, err := ctx.ParseIR(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer m.Dispose()
+
+	fn := m.NamedFunction("foo")
+	sw := fn.EntryBasicBlock().FirstInstruction()
+
+	if n := sw.SuccessorsCount(); n != 3 {
+		t.Fatalf("expected 3 successors (default + 2 cases), got %d", n)
+	}
+	if got := sw.Successor(0).AsValue().Name(); got != "default" {
+		t.Errorf("expected default destination %q, got %q", "default", got)
+	}
+
+	wantCaseValues := []uint64{0, 5}
+	wantCaseDests := []string{"case0", "case1"}
+	for i, want := range wantCaseValues {
+		successor := i + 1
+		val := sw.GetSwitchCaseValue(successor)
+		if got := val.ZExtValue(); got != want {
+			t.Errorf("case %d: expected value %d, got %d", i, want, got)
+		}
+		if got := sw.Successor(successor).AsValue().Name(); got != wantCaseDests[i] {
+			t.Errorf("case %d: expected destination %q, got %q", i, wantCaseDests[i], got)
+		}
+	}
+}