diff --git a/MODULE.bazel b/MODULE.bazel
index 35a11f23ce79..47aa57605ffc 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -33,6 +33,7 @@ bazel_dep(name = "bazel_skylib", version = "1.7.1")
 bazel_dep(name = "google_benchmark", version = "1.8.5")
 bazel_dep(name = "googletest", version = "1.15.2")
 bazel_dep(name = "re2", version = "2024-07-02.bcr.1")
+bazel_dep(name = "rules_cc", version = "0.1.1")
 bazel_dep(name = "rules_pkg", version = "1.0.1")
 bazel_dep(name = "rules_shell", version = "0.4.1")
 bazel_dep(name = "tree-sitter-bazel", version = "0.24.4")
@@ -67,8 +68,6 @@ git_override(
     remote = "https://github.com/google/tcmalloc.git",
 )
 
-bazel_dep(name = "rules_cc", version = "0.1.1")
-
 bazel_dep(name = "bazel_clang_tidy", dev_dependency = True)
 git_override(
     module_name = "bazel_clang_tidy",
@@ -115,7 +114,7 @@ bazel_dep(name = "zstd", version = "1.5.6", repo_name = "llvm_zstd")
 # We pin to specific upstream commits and try to track top-of-tree reasonably
 # closely rather than pinning to a specific release.
 # HEAD as of 2025-05-02.
-llvm_project_version = "12778374881e84bf2a8571f2815ed1e94ffe5709"
+llvm_project_version = "98763433e66dd91bf5f10b1daf03d9373f07912a"
 
 # Load a repository for the raw llvm-project, pre-overlay.
 http_archive(
@@ -127,7 +126,7 @@ http_archive(
         "@carbon//bazel/llvm_project:0002_Added_Bazel_build_for_compiler_rt_fuzzer.patch",
         "@carbon//bazel/llvm_project:0003_Comment_out_unloaded_proto_library_dependencies.patch",
     ],
-    sha256 = "8466760c8d69c5d3a1d2561813f47fa9a6962076adfb2b3f7aa0a69417b36c52",
+    sha256 = "140ea04e8b1266a21926da5f1cbeee182c75086eaff2c0bf963538fea4d39014",
     strip_prefix = "llvm-project-{0}".format(llvm_project_version),
     urls = ["https://github.com/llvm/llvm-project/archive/{0}.tar.gz".format(llvm_project_version)],
 )
diff --git a/toolchain/lower/testdata/array/base.carbon b/toolchain/lower/testdata/array/base.carbon
index 283a211efbd6..863537962400 100644
--- a/toolchain/lower/testdata/array/base.carbon
+++ b/toolchain/lower/testdata/array/base.carbon
@@ -73,7 +73,6 @@ fn Run() {
 // CHECK:STDOUT: declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 0, 2, 1, 3, 4, 5, 6, 7 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 4, 3, 2, 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @llvm.memcpy.p0.p0.i64, { 3, 2, 1, 0 }
 // CHECK:STDOUT:
diff --git a/toolchain/lower/testdata/class/virtual.carbon b/toolchain/lower/testdata/class/virtual.carbon
index 7b0711cce652..da4e720d3b1a 100644
--- a/toolchain/lower/testdata/class/virtual.carbon
+++ b/toolchain/lower/testdata/class/virtual.carbon
@@ -169,7 +169,6 @@ base class Base(T:! type) {
 // CHECK:STDOUT: declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 1, 3, 0, 2, 4, 5 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 3, 2, 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @llvm.memcpy.p0.p0.i64, { 2, 1, 0 }
 // CHECK:STDOUT:
@@ -234,7 +233,6 @@ base class Base(T:! type) {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(i64 immarg, ptr captures(none)) #0
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 0, 2, 3, 1, 4, 5 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 2, 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
diff --git a/toolchain/lower/testdata/function/call/tuple_param_with_return_slot.carbon b/toolchain/lower/testdata/function/call/tuple_param_with_return_slot.carbon
index ab3c481c3a23..2239ae1d8b84 100644
--- a/toolchain/lower/testdata/function/call/tuple_param_with_return_slot.carbon
+++ b/toolchain/lower/testdata/function/call/tuple_param_with_return_slot.carbon
@@ -44,9 +44,6 @@ fn Main() {
 // CHECK:STDOUT:   ret void, !dbg !14
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 3, 0, 1, 2 }
-// CHECK:STDOUT:
 // CHECK:STDOUT: !llvm.module.flags = !{!0, !1}
 // CHECK:STDOUT: !llvm.dbg.cu = !{!2}
 // CHECK:STDOUT:
diff --git a/toolchain/lower/testdata/global/simple_init.carbon b/toolchain/lower/testdata/global/simple_init.carbon
index 67d9c68d31fe..49b8996159c4 100644
--- a/toolchain/lower/testdata/global/simple_init.carbon
+++ b/toolchain/lower/testdata/global/simple_init.carbon
@@ -21,9 +21,6 @@ var a: i32 = 0;
 // CHECK:STDOUT:   ret void, !dbg !8
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 0, { 1, 0, 2 }
-// CHECK:STDOUT:
 // CHECK:STDOUT: !llvm.module.flags = !{!0, !1}
 // CHECK:STDOUT: !llvm.dbg.cu = !{!2}
 // CHECK:STDOUT:
diff --git a/toolchain/lower/testdata/global/simple_with_fun.carbon b/toolchain/lower/testdata/global/simple_with_fun.carbon
index a2214c070c0c..20f9aae83f65 100644
--- a/toolchain/lower/testdata/global/simple_with_fun.carbon
+++ b/toolchain/lower/testdata/global/simple_with_fun.carbon
@@ -32,9 +32,6 @@ var a: i32 = test_a();
 // CHECK:STDOUT:   ret void, !dbg !11
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 0, { 1, 0, 2 }
-// CHECK:STDOUT:
 // CHECK:STDOUT: !llvm.module.flags = !{!0, !1}
 // CHECK:STDOUT: !llvm.dbg.cu = !{!2}
 // CHECK:STDOUT:
diff --git a/toolchain/lower/testdata/index/array_element_access.carbon b/toolchain/lower/testdata/index/array_element_access.carbon
index a8c0b8b5d55c..9fb764d01947 100644
--- a/toolchain/lower/testdata/index/array_element_access.carbon
+++ b/toolchain/lower/testdata/index/array_element_access.carbon
@@ -80,7 +80,6 @@ fn Run() {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(i64 immarg, ptr captures(none)) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 0, 1, 4, 6, 7, 2, 3, 5, 8, 9, 10 }
 // CHECK:STDOUT: uselistorder ptr @llvm.memcpy.p0.p0.i64, { 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 3, 2, 1, 0 }
 // CHECK:STDOUT:
diff --git a/toolchain/lower/testdata/let/tuple.carbon b/toolchain/lower/testdata/let/tuple.carbon
index 1159af81a7d8..765e20297910 100644
--- a/toolchain/lower/testdata/let/tuple.carbon
+++ b/toolchain/lower/testdata/let/tuple.carbon
@@ -75,7 +75,6 @@ fn F() -> i32 {
 // CHECK:STDOUT: declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 11, 13, 14 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @llvm.memcpy.p0.p0.i64, { 1, 0 }
 // CHECK:STDOUT:
diff --git a/toolchain/lower/testdata/operators/overloaded.carbon b/toolchain/lower/testdata/operators/overloaded.carbon
index 00881352d180..0b248bc6e658 100644
--- a/toolchain/lower/testdata/operators/overloaded.carbon
+++ b/toolchain/lower/testdata/operators/overloaded.carbon
@@ -88,9 +88,6 @@ fn Calculate(a: Number, b: Number) -> Number {
 // CHECK:STDOUT:   ret void, !dbg !23
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i1 true, { 2, 0, 1, 3, 4 }
-// CHECK:STDOUT:
 // CHECK:STDOUT: !llvm.module.flags = !{!0, !1}
 // CHECK:STDOUT: !llvm.dbg.cu = !{!2}
 // CHECK:STDOUT:
diff --git a/toolchain/lower/testdata/struct/member_access.carbon b/toolchain/lower/testdata/struct/member_access.carbon
index 3b3bfebed14a..1a9bdf90beb7 100644
--- a/toolchain/lower/testdata/struct/member_access.carbon
+++ b/toolchain/lower/testdata/struct/member_access.carbon
@@ -46,7 +46,6 @@ fn Run() -> i32 {
 // CHECK:STDOUT: declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 1, 3, 0, 2, 4, 5 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 2, 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
diff --git a/toolchain/lower/testdata/struct/two_entries.carbon b/toolchain/lower/testdata/struct/two_entries.carbon
index 68f51c4dabe1..aa2889dcbd68 100644
--- a/toolchain/lower/testdata/struct/two_entries.carbon
+++ b/toolchain/lower/testdata/struct/two_entries.carbon
@@ -46,7 +46,6 @@ fn Run() -> i32 {
 // CHECK:STDOUT: declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 0, 1, 3, 2, 4, 5 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
diff --git a/toolchain/lower/testdata/tuple/access/element_access.carbon b/toolchain/lower/testdata/tuple/access/element_access.carbon
index 46fd020b96a2..112f11790f1e 100644
--- a/toolchain/lower/testdata/tuple/access/element_access.carbon
+++ b/toolchain/lower/testdata/tuple/access/element_access.carbon
@@ -48,7 +48,6 @@ fn Run() -> i32 {
 // CHECK:STDOUT: declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 2, 0, 1, 3, 4 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 2, 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
diff --git a/toolchain/lower/testdata/tuple/one_entry.carbon b/toolchain/lower/testdata/tuple/one_entry.carbon
index 5dbb654cd2e4..f7d3defc8a6a 100644
--- a/toolchain/lower/testdata/tuple/one_entry.carbon
+++ b/toolchain/lower/testdata/tuple/one_entry.carbon
@@ -35,7 +35,6 @@ fn Run() -> i32 {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(i64 immarg, ptr captures(none)) #0
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 2, 0, 1 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
diff --git a/toolchain/lower/testdata/tuple/two_entries.carbon b/toolchain/lower/testdata/tuple/two_entries.carbon
index 246cc246190d..ec270cfff7e6 100644
--- a/toolchain/lower/testdata/tuple/two_entries.carbon
+++ b/toolchain/lower/testdata/tuple/two_entries.carbon
@@ -46,7 +46,6 @@ fn Run() -> i32 {
 // CHECK:STDOUT: declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 0, 1, 3, 2, 4 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
diff --git a/toolchain/lower/testdata/var/nested.carbon b/toolchain/lower/testdata/var/nested.carbon
index 38d93ec4dc29..7340eaec4bda 100644
--- a/toolchain/lower/testdata/var/nested.carbon
+++ b/toolchain/lower/testdata/var/nested.carbon
@@ -48,7 +48,6 @@ fn Run() -> i32 {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(i64 immarg, ptr captures(none)) #0
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder i32 1, { 1, 0, 2 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }