diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5f659a1c3060c..a0d9eb8c45292 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -56,7 +56,7 @@ jobs:
           - name: mingw-check-tidy
             os: ubuntu-20.04-4core-16gb
             env: {}
-          - name: x86_64-gnu-llvm-15
+          - name: x86_64-gnu-llvm-16
             env:
               ENABLE_GCC_CODEGEN: "1"
             os: ubuntu-20.04-16core-64gb
@@ -302,10 +302,6 @@ jobs:
             env:
               RUST_BACKTRACE: 1
             os: ubuntu-20.04-8core-32gb
-          - name: x86_64-gnu-llvm-15
-            env:
-              RUST_BACKTRACE: 1
-            os: ubuntu-20.04-8core-32gb
           - name: x86_64-gnu-nopt
             os: ubuntu-20.04-4core-16gb
             env: {}
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs
index 242c6aed906b4..bb7730f08e949 100644
--- a/compiler/rustc_codegen_llvm/src/context.rs
+++ b/compiler/rustc_codegen_llvm/src/context.rs
@@ -134,18 +134,6 @@ pub unsafe fn create_module<'ll>(
 
     let mut target_data_layout = sess.target.data_layout.to_string();
     let llvm_version = llvm_util::get_version();
-    if llvm_version < (16, 0, 0) {
-        if sess.target.arch == "s390x" {
-            // LLVM 16 data layout changed to always set 64-bit vector alignment,
-            // which is conditional in earlier LLVM versions.
-            // https://reviews.llvm.org/D131158 for the discussion.
-            target_data_layout = target_data_layout.replace("-v128:64", "");
-        } else if sess.target.arch == "riscv64" {
-            // LLVM 16 introduced this change so as to produce more efficient code.
-            // See https://reviews.llvm.org/D116735 for the discussion.
-            target_data_layout = target_data_layout.replace("-n32:64-", "-n64-");
-        }
-    }
     if llvm_version < (17, 0, 0) {
         if sess.target.arch.starts_with("powerpc") {
             // LLVM 17 specifies function pointer alignment for ppc:
diff --git a/compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h b/compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h
index 142384e6d0ca2..ad97ede8e9c3b 100644
--- a/compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h
+++ b/compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h
@@ -42,11 +42,7 @@
 #include "llvm/IR/IRPrintingPasses.h"
 #include "llvm/Linker/Linker.h"
 
-#if LLVM_VERSION_GE(16, 0)
 #include "llvm/TargetParser/Triple.h"
-#else
-#include "llvm/ADT/Triple.h"
-#endif
 
 extern "C" void LLVMRustSetLastError(const char *);
 
diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index 31565db1b7929..25af07ff3d373 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -204,11 +204,7 @@ enum class LLVMRustCodeModel {
   None,
 };
 
-#if LLVM_VERSION_LT(16, 0)
-static Optional<CodeModel::Model>
-#else
 static std::optional<CodeModel::Model>
-#endif
 fromRust(LLVMRustCodeModel Model) {
   switch (Model) {
   case LLVMRustCodeModel::Tiny:
@@ -222,11 +218,7 @@ fromRust(LLVMRustCodeModel Model) {
   case LLVMRustCodeModel::Large:
     return CodeModel::Large;
   case LLVMRustCodeModel::None:
-#if LLVM_VERSION_LT(16, 0)
-    return None;
-#else
     return std::nullopt;
-#endif
   default:
     report_fatal_error("Bad CodeModel.");
   }
@@ -452,7 +444,6 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
   if (OutputObjFile) {
       Options.ObjectFilenameForDebug = OutputObjFile;
   }
-#if LLVM_VERSION_GE(16, 0)
   if (!strcmp("zlib", DebugInfoCompression) && llvm::compression::zlib::isAvailable()) {
     Options.CompressDebugSections = DebugCompressionType::Zlib;
   } else if (!strcmp("zstd", DebugInfoCompression) && llvm::compression::zstd::isAvailable()) {
@@ -460,7 +451,6 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
   } else if (!strcmp("none", DebugInfoCompression)) {
     Options.CompressDebugSections = DebugCompressionType::None;
   }
-#endif
 
   Options.RelaxELFRelocations = RelaxELFRelocations;
   Options.UseInitArray = UseInitArray;
@@ -734,22 +724,14 @@ LLVMRustOptimize(
   bool DebugPassManager = false;
 
   PassInstrumentationCallbacks PIC;
-#if LLVM_VERSION_LT(16, 0)
-  StandardInstrumentations SI(DebugPassManager);
-#else
   StandardInstrumentations SI(TheModule->getContext(), DebugPassManager);
-#endif
   SI.registerCallbacks(PIC);
 
   if (LlvmSelfProfiler){
     LLVMSelfProfileInitializeCallbacks(PIC,LlvmSelfProfiler,BeforePassCallback,AfterPassCallback);
   }
 
-#if LLVM_VERSION_LT(16, 0)
-  Optional<PGOOptions> PGOOpt;
-#else
   std::optional<PGOOptions> PGOOpt;
-#endif
 #if LLVM_VERSION_GE(17, 0)
   auto FS = vfs::getRealFileSystem();
 #endif
@@ -882,12 +864,7 @@ LLVMRustOptimize(
           /*EagerChecks=*/true);
       OptimizerLastEPCallbacks.push_back(
         [Options](ModulePassManager &MPM, OptimizationLevel Level) {
-#if LLVM_VERSION_LT(16, 0)
-          MPM.addPass(ModuleMemorySanitizerPass(Options));
-          MPM.addPass(createModuleToFunctionPassAdaptor(MemorySanitizerPass(Options)));
-#else
           MPM.addPass(MemorySanitizerPass(Options));
-#endif
         }
       );
     }
@@ -912,11 +889,7 @@ LLVMRustOptimize(
             /*UseAfterScope=*/true,
             AsanDetectStackUseAfterReturnMode::Runtime,
           };
-#if LLVM_VERSION_LT(16, 0)
-          MPM.addPass(ModuleAddressSanitizerPass(opts));
-#else
           MPM.addPass(AddressSanitizerPass(opts));
-#endif
         }
       );
     }
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index 7ada2eff593c6..bf870e28acd2c 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -14,18 +14,13 @@
 #include "llvm/Remarks/RemarkSerializer.h"
 #include "llvm/Remarks/RemarkFormat.h"
 #include "llvm/Support/ToolOutputFile.h"
-#if LLVM_VERSION_GE(16, 0)
 #include "llvm/Support/ModRef.h"
-#endif
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/COFFImportFile.h"
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/Pass.h"
 #include "llvm/Bitcode/BitcodeWriter.h"
 #include "llvm/Support/Signals.h"
-#if LLVM_VERSION_LT(16, 0)
-#include "llvm/ADT/Optional.h"
-#endif
 
 #include <iostream>
 
@@ -347,13 +342,7 @@ extern "C" LLVMAttributeRef LLVMRustCreateUWTableAttr(LLVMContextRef C, bool Asy
 }
 
 extern "C" LLVMAttributeRef LLVMRustCreateAllocSizeAttr(LLVMContextRef C, uint32_t ElementSizeArg) {
-  return wrap(Attribute::getWithAllocSizeArgs(*unwrap(C), ElementSizeArg,
-#if LLVM_VERSION_LT(16, 0)
-                                              None
-#else
-                                              std::nullopt
-#endif
-                                              ));
+  return wrap(Attribute::getWithAllocSizeArgs(*unwrap(C), ElementSizeArg, std::nullopt));
 }
 
 // These values **must** match ffi::AllocKindFlags.
@@ -416,7 +405,6 @@ enum class LLVMRustMemoryEffects {
 
 extern "C" LLVMAttributeRef LLVMRustCreateMemoryEffectsAttr(LLVMContextRef C,
                                                             LLVMRustMemoryEffects Effects) {
-#if LLVM_VERSION_GE(16, 0)
   switch (Effects) {
     case LLVMRustMemoryEffects::None:
       return wrap(Attribute::getWithMemoryEffects(*unwrap(C), MemoryEffects::none()));
@@ -428,18 +416,6 @@ extern "C" LLVMAttributeRef LLVMRustCreateMemoryEffectsAttr(LLVMContextRef C,
     default:
       report_fatal_error("bad MemoryEffects.");
   }
-#else
-  switch (Effects) {
-    case LLVMRustMemoryEffects::None:
-      return wrap(Attribute::get(*unwrap(C), Attribute::ReadNone));
-    case LLVMRustMemoryEffects::ReadOnly:
-      return wrap(Attribute::get(*unwrap(C), Attribute::ReadOnly));
-    case LLVMRustMemoryEffects::InaccessibleMemOnly:
-      return wrap(Attribute::get(*unwrap(C), Attribute::InaccessibleMemOnly));
-    default:
-      report_fatal_error("bad MemoryEffects.");
-  }
-#endif
 }
 
 // Enable a fast-math flag
@@ -726,18 +702,10 @@ enum class LLVMRustChecksumKind {
   SHA256,
 };
 
-#if LLVM_VERSION_LT(16, 0)
-static Optional<DIFile::ChecksumKind> fromRust(LLVMRustChecksumKind Kind) {
-#else
 static std::optional<DIFile::ChecksumKind> fromRust(LLVMRustChecksumKind Kind) {
-#endif
   switch (Kind) {
   case LLVMRustChecksumKind::None:
-#if LLVM_VERSION_LT(16, 0)
-    return None;
-#else
     return std::nullopt;
-#endif
   case LLVMRustChecksumKind::MD5:
     return DIFile::ChecksumKind::CSK_MD5;
   case LLVMRustChecksumKind::SHA1:
@@ -810,17 +778,8 @@ extern "C" LLVMMetadataRef LLVMRustDIBuilderCreateFile(
     const char *Directory, size_t DirectoryLen, LLVMRustChecksumKind CSKind,
     const char *Checksum, size_t ChecksumLen) {
 
-#if LLVM_VERSION_LT(16, 0)
-  Optional<DIFile::ChecksumKind> llvmCSKind = fromRust(CSKind);
-#else
   std::optional<DIFile::ChecksumKind> llvmCSKind = fromRust(CSKind);
-#endif
-
-#if LLVM_VERSION_LT(16, 0)
-  Optional<DIFile::ChecksumInfo<StringRef>> CSInfo{};
-#else
   std::optional<DIFile::ChecksumInfo<StringRef>> CSInfo{};
-#endif
   if (llvmCSKind)
     CSInfo.emplace(*llvmCSKind, StringRef{Checksum, ChecksumLen});
   return wrap(Builder->createFile(StringRef(Filename, FilenameLen),
@@ -2053,17 +2012,9 @@ extern "C" bool LLVMRustIsNonGVFunctionPointerTy(LLVMValueRef V) {
 }
 
 extern "C" bool LLVMRustLLVMHasZlibCompressionForDebugSymbols() {
-#if LLVM_VERSION_GE(16, 0)
   return llvm::compression::zlib::isAvailable();
-#else
-  return false;
-#endif
 }
 
 extern "C" bool LLVMRustLLVMHasZstdCompressionForDebugSymbols() {
-#if LLVM_VERSION_GE(16, 0)
   return llvm::compression::zstd::isAvailable();
-#else
-  return false;
-#endif
 }
diff --git a/compiler/rustc_target/src/spec/mod.rs b/compiler/rustc_target/src/spec/mod.rs
index 9de8aa7c71269..c54698bbf013a 100644
--- a/compiler/rustc_target/src/spec/mod.rs
+++ b/compiler/rustc_target/src/spec/mod.rs
@@ -1155,10 +1155,6 @@ pub enum StackProbeType {
 }
 
 impl StackProbeType {
-    // LLVM X86 targets (ix86 and x86_64) can use inline-asm stack probes starting with LLVM 16.
-    // Notable past issues were rust#83139 (fixed in 14) and rust#84667 (fixed in 16).
-    const X86: Self = Self::InlineOrCall { min_llvm_version_for_inline: (16, 0, 0) };
-
     fn from_json(json: &Json) -> Result<Self, String> {
         let object = json.as_object().ok_or_else(|| "expected a JSON object")?;
         let kind = object
diff --git a/compiler/rustc_target/src/spec/targets/i386_apple_ios.rs b/compiler/rustc_target/src/spec/targets/i386_apple_ios.rs
index ed2c990ffa64b..ce0d604f57c76 100644
--- a/compiler/rustc_target/src/spec/targets/i386_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/targets/i386_apple_ios.rs
@@ -16,7 +16,7 @@ pub fn target() -> Target {
         arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(64),
-            stack_probes: StackProbeType::X86,
+            stack_probes: StackProbeType::Inline,
             ..opts("ios", arch)
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/i586_pc_nto_qnx700.rs b/compiler/rustc_target/src/spec/targets/i586_pc_nto_qnx700.rs
index 06089391623bb..3ebf4bcf5231d 100644
--- a/compiler/rustc_target/src/spec/targets/i586_pc_nto_qnx700.rs
+++ b/compiler/rustc_target/src/spec/targets/i586_pc_nto_qnx700.rs
@@ -16,7 +16,7 @@ pub fn target() -> Target {
                 &["-Vgcc_ntox86_cxx"],
             ),
             env: "nto70".into(),
-            stack_probes: StackProbeType::X86,
+            stack_probes: StackProbeType::Inline,
             ..base::nto_qnx::opts()
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/i686_apple_darwin.rs b/compiler/rustc_target/src/spec/targets/i686_apple_darwin.rs
index 242fe5ed98a90..c4c9023419d6b 100644
--- a/compiler/rustc_target/src/spec/targets/i686_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_apple_darwin.rs
@@ -7,7 +7,7 @@ pub fn target() -> Target {
     let mut base = opts("macos", arch);
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Darwin(Cc::Yes, Lld::No), &["-m32"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.frame_pointer = FramePointer::Always;
 
     Target {
diff --git a/compiler/rustc_target/src/spec/targets/i686_linux_android.rs b/compiler/rustc_target/src/spec/targets/i686_linux_android.rs
index 987265598ebcd..79471040f0da2 100644
--- a/compiler/rustc_target/src/spec/targets/i686_linux_android.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_linux_android.rs
@@ -11,7 +11,7 @@ pub fn target() -> Target {
     // https://developer.android.com/ndk/guides/abis.html#x86
     base.cpu = "pentiumpro".into();
     base.features = "+mmx,+sse,+sse2,+sse3,+ssse3".into();
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "i686-linux-android".into(),
diff --git a/compiler/rustc_target/src/spec/targets/i686_unknown_freebsd.rs b/compiler/rustc_target/src/spec/targets/i686_unknown_freebsd.rs
index 70aa0b47962e9..927b2ab877ddf 100644
--- a/compiler/rustc_target/src/spec/targets/i686_unknown_freebsd.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_unknown_freebsd.rs
@@ -5,7 +5,7 @@ pub fn target() -> Target {
     base.cpu = "pentium4".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32", "-Wl,-znotext"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "i686-unknown-freebsd".into(),
diff --git a/compiler/rustc_target/src/spec/targets/i686_unknown_haiku.rs b/compiler/rustc_target/src/spec/targets/i686_unknown_haiku.rs
index 9715f6c21d909..bc7fd6fbc68cd 100644
--- a/compiler/rustc_target/src/spec/targets/i686_unknown_haiku.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_unknown_haiku.rs
@@ -5,7 +5,7 @@ pub fn target() -> Target {
     base.cpu = "pentium4".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "i686-unknown-haiku".into(),
diff --git a/compiler/rustc_target/src/spec/targets/i686_unknown_linux_gnu.rs b/compiler/rustc_target/src/spec/targets/i686_unknown_linux_gnu.rs
index 0ca058b2fd2a5..3b7be48dbbc56 100644
--- a/compiler/rustc_target/src/spec/targets/i686_unknown_linux_gnu.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_unknown_linux_gnu.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.max_atomic_width = Some(64);
     base.supported_sanitizers = SanitizerSet::ADDRESS;
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "i686-unknown-linux-gnu".into(),
diff --git a/compiler/rustc_target/src/spec/targets/i686_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/targets/i686_unknown_linux_musl.rs
index ce0df3a72344c..ef58b4fb45881 100644
--- a/compiler/rustc_target/src/spec/targets/i686_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_unknown_linux_musl.rs
@@ -5,7 +5,7 @@ pub fn target() -> Target {
     base.cpu = "pentium4".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32", "-Wl,-melf_i386"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     // The unwinder used by i686-unknown-linux-musl, the LLVM libunwind
     // implementation, apparently relies on frame pointers existing... somehow.
diff --git a/compiler/rustc_target/src/spec/targets/i686_unknown_netbsd.rs b/compiler/rustc_target/src/spec/targets/i686_unknown_netbsd.rs
index 2a3ac5932d351..5f3afbe5afdcd 100644
--- a/compiler/rustc_target/src/spec/targets/i686_unknown_netbsd.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_unknown_netbsd.rs
@@ -5,7 +5,7 @@ pub fn target() -> Target {
     base.cpu = "pentium4".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "i686-unknown-netbsdelf".into(),
diff --git a/compiler/rustc_target/src/spec/targets/i686_unknown_openbsd.rs b/compiler/rustc_target/src/spec/targets/i686_unknown_openbsd.rs
index 45883542beade..f44584a10be53 100644
--- a/compiler/rustc_target/src/spec/targets/i686_unknown_openbsd.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_unknown_openbsd.rs
@@ -5,7 +5,7 @@ pub fn target() -> Target {
     base.cpu = "pentium4".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32", "-fuse-ld=lld"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "i686-unknown-openbsd".into(),
diff --git a/compiler/rustc_target/src/spec/targets/i686_wrs_vxworks.rs b/compiler/rustc_target/src/spec/targets/i686_wrs_vxworks.rs
index 965a895972c6e..ee501c5165e0e 100644
--- a/compiler/rustc_target/src/spec/targets/i686_wrs_vxworks.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_wrs_vxworks.rs
@@ -5,7 +5,7 @@ pub fn target() -> Target {
     base.cpu = "pentium4".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "i686-unknown-linux-gnu".into(),
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_apple_darwin.rs b/compiler/rustc_target/src/spec/targets/x86_64_apple_darwin.rs
index 9170a10d254b4..81173a16f96f7 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_apple_darwin.rs
@@ -8,7 +8,7 @@ pub fn target() -> Target {
     base.max_atomic_width = Some(128); // penryn+ supports cmpxchg16b
     base.frame_pointer = FramePointer::Always;
     base.add_pre_link_args(LinkerFlavor::Darwin(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.supported_sanitizers =
         SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::LEAK | SanitizerSet::THREAD;
 
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_apple_ios.rs b/compiler/rustc_target/src/spec/targets/x86_64_apple_ios.rs
index d9f3f7de655c0..221635526d104 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_apple_ios.rs
@@ -14,7 +14,7 @@ pub fn target() -> Target {
         arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(128),
-            stack_probes: StackProbeType::X86,
+            stack_probes: StackProbeType::Inline,
             ..base
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_apple_ios_macabi.rs b/compiler/rustc_target/src/spec/targets/x86_64_apple_ios_macabi.rs
index 5e6fbac34d718..5f6b4b500d07b 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_apple_ios_macabi.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_apple_ios_macabi.rs
@@ -17,7 +17,7 @@ pub fn target() -> Target {
         arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(128),
-            stack_probes: StackProbeType::X86,
+            stack_probes: StackProbeType::Inline,
             ..base
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_apple_tvos.rs b/compiler/rustc_target/src/spec/targets/x86_64_apple_tvos.rs
index 1c4d9196c1852..a7d5f28e0e500 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_apple_tvos.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_apple_tvos.rs
@@ -11,7 +11,7 @@ pub fn target() -> Target {
         arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(128),
-            stack_probes: StackProbeType::X86,
+            stack_probes: StackProbeType::Inline,
             ..opts("tvos", arch)
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_apple_watchos_sim.rs b/compiler/rustc_target/src/spec/targets/x86_64_apple_watchos_sim.rs
index 9faf9b1ca3f78..3c5bf30ef5fa3 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_apple_watchos_sim.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_apple_watchos_sim.rs
@@ -11,7 +11,7 @@ pub fn target() -> Target {
         arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(128),
-            stack_probes: StackProbeType::X86,
+            stack_probes: StackProbeType::Inline,
             ..opts("watchos", arch)
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_linux_android.rs b/compiler/rustc_target/src/spec/targets/x86_64_linux_android.rs
index 6cffda44fa9eb..0e6d41abc9b40 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_linux_android.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_linux_android.rs
@@ -10,7 +10,7 @@ pub fn target() -> Target {
     base.features = "+mmx,+sse,+sse2,+sse3,+ssse3,+sse4.1,+sse4.2,+popcnt".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.supports_xray = true;
 
     Target {
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_pc_solaris.rs b/compiler/rustc_target/src/spec/targets/x86_64_pc_solaris.rs
index ca6a6dc500b8b..f15ad8dda63bc 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_pc_solaris.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_pc_solaris.rs
@@ -7,7 +7,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.vendor = "pc".into();
     base.max_atomic_width = Some(64);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.supported_sanitizers = SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::THREAD;
 
     Target {
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_sun_solaris.rs b/compiler/rustc_target/src/spec/targets/x86_64_sun_solaris.rs
index cca099d3bbf65..a1b44236e93b4 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_sun_solaris.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_sun_solaris.rs
@@ -7,7 +7,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.vendor = "sun".into();
     base.max_atomic_width = Some(64);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "x86_64-pc-solaris".into(),
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unikraft_linux_musl.rs b/compiler/rustc_target/src/spec/targets/x86_64_unikraft_linux_musl.rs
index c12cb1ab00e0a..e6159fca3aeaf 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unikraft_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unikraft_linux_musl.rs
@@ -12,7 +12,7 @@ pub fn target() -> Target {
             plt_by_default: false,
             pre_link_args: TargetOptions::link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]),
             max_atomic_width: Some(64),
-            stack_probes: StackProbeType::X86,
+            stack_probes: StackProbeType::Inline,
             ..base::unikraft_linux_musl::opts()
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_dragonfly.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_dragonfly.rs
index 68d1a755b7921..80adb8fa2d951 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_dragonfly.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_dragonfly.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "x86_64-unknown-dragonfly".into(),
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_freebsd.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_freebsd.rs
index e3f29fa5afaf7..fa32103536708 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_freebsd.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_freebsd.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.supported_sanitizers =
         SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::MEMORY | SanitizerSet::THREAD;
     base.supports_xray = true;
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_fuchsia.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_fuchsia.rs
index c8850d703e359..f0515615b1951 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_fuchsia.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_fuchsia.rs
@@ -5,7 +5,7 @@ pub fn target() -> Target {
     base.cpu = "x86-64".into();
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.supported_sanitizers = SanitizerSet::ADDRESS | SanitizerSet::CFI;
 
     Target {
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_haiku.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_haiku.rs
index ca55e6514ddd9..0f927be962bfb 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_haiku.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_haiku.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     // This option is required to build executables on Haiku x86_64
     base.position_independent_executables = true;
 
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_hermit.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_hermit.rs
index 3cc50d40dda6c..df191f515bd68 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_hermit.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_hermit.rs
@@ -12,7 +12,7 @@ pub fn target() -> Target {
             features: "+rdrnd,+rdseed".into(),
             plt_by_default: false,
             max_atomic_width: Some(64),
-            stack_probes: StackProbeType::X86,
+            stack_probes: StackProbeType::Inline,
             ..base::hermit::opts()
         },
     }
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnu.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnu.rs
index 80e267c163fa0..bf10f7e5d2de3 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnu.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnu.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.static_position_independent_executables = true;
     base.supported_sanitizers = SanitizerSet::ADDRESS
         | SanitizerSet::CFI
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnux32.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnux32.rs
index 622bfe8bbe8e4..1856c6afd52be 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnux32.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnux32.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.abi = "x32".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-mx32"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.has_thread_local = false;
     // BUG(GabrielMajeri): disabling the PLT on x86_64 Linux with x32 ABI
     // breaks code gen. See LLVM bug 36743
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_musl.rs
index d74ff466a0158..8dc5503e336a6 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_musl.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.static_position_independent_executables = true;
     base.supported_sanitizers = SanitizerSet::ADDRESS
         | SanitizerSet::CFI
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_ohos.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_ohos.rs
index 87b004df00186..35862656aa2fd 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_ohos.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_ohos.rs
@@ -5,7 +5,7 @@ pub fn target() -> Target {
     base.cpu = "x86-64".into();
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.static_position_independent_executables = true;
     base.supported_sanitizers = SanitizerSet::ADDRESS
         | SanitizerSet::CFI
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_netbsd.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_netbsd.rs
index 04060513abc84..e2cee0513babf 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_netbsd.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_netbsd.rs
@@ -8,7 +8,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.supported_sanitizers = SanitizerSet::ADDRESS
         | SanitizerSet::CFI
         | SanitizerSet::LEAK
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_none.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_none.rs
index 9aa95a35f8e55..8f7655d8ccd35 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_none.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_none.rs
@@ -12,7 +12,7 @@ pub fn target() -> Target {
         cpu: "x86-64".into(),
         plt_by_default: false,
         max_atomic_width: Some(64),
-        stack_probes: StackProbeType::X86,
+        stack_probes: StackProbeType::Inline,
         position_independent_executables: true,
         static_position_independent_executables: true,
         relro_level: RelroLevel::Full,
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_openbsd.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_openbsd.rs
index 5e6e7efb2de83..1133b50f3d223 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_openbsd.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_openbsd.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.supports_xray = true;
 
     Target {
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_unknown_redox.rs b/compiler/rustc_target/src/spec/targets/x86_64_unknown_redox.rs
index 382ff71f019c1..c1f573112920d 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_unknown_redox.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_unknown_redox.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
 
     Target {
         llvm_target: "x86_64-unknown-redox".into(),
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_wrs_vxworks.rs b/compiler/rustc_target/src/spec/targets/x86_64_wrs_vxworks.rs
index 4b221fe6959fa..765239bdd39c2 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_wrs_vxworks.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_wrs_vxworks.rs
@@ -6,7 +6,7 @@ pub fn target() -> Target {
     base.plt_by_default = false;
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.disable_redzone = true;
 
     Target {
diff --git a/compiler/rustc_target/src/spec/targets/x86_64h_apple_darwin.rs b/compiler/rustc_target/src/spec/targets/x86_64h_apple_darwin.rs
index a30e9d17cef87..32d15c186787d 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64h_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64h_apple_darwin.rs
@@ -8,7 +8,7 @@ pub fn target() -> Target {
     base.max_atomic_width = Some(128);
     base.frame_pointer = FramePointer::Always;
     base.add_pre_link_args(LinkerFlavor::Darwin(Cc::Yes, Lld::No), &["-m64"]);
-    base.stack_probes = StackProbeType::X86;
+    base.stack_probes = StackProbeType::Inline;
     base.supported_sanitizers =
         SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::LEAK | SanitizerSet::THREAD;
 
diff --git a/src/bootstrap/src/core/build_steps/llvm.rs b/src/bootstrap/src/core/build_steps/llvm.rs
index a1f6fac8a518a..6fa86e95cbc3c 100644
--- a/src/bootstrap/src/core/build_steps/llvm.rs
+++ b/src/bootstrap/src/core/build_steps/llvm.rs
@@ -560,11 +560,11 @@ fn check_llvm_version(builder: &Builder<'_>, llvm_config: &Path) {
     let version = output(cmd.arg("--version"));
     let mut parts = version.split('.').take(2).filter_map(|s| s.parse::<u32>().ok());
     if let (Some(major), Some(_minor)) = (parts.next(), parts.next()) {
-        if major >= 15 {
+        if major >= 16 {
             return;
         }
     }
-    panic!("\n\nbad LLVM version: {version}, need >=15.0\n\n")
+    panic!("\n\nbad LLVM version: {version}, need >=16.0\n\n")
 }
 
 fn configure_cmake(
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-15/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-15/Dockerfile
deleted file mode 100644
index cefdcad764397..0000000000000
--- a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-15/Dockerfile
+++ /dev/null
@@ -1,59 +0,0 @@
-FROM ubuntu:22.04
-
-ARG DEBIAN_FRONTEND=noninteractive
-
-RUN apt-get update && apt-get install -y --no-install-recommends \
-  g++ \
-  gcc-multilib \
-  make \
-  ninja-build \
-  file \
-  curl \
-  ca-certificates \
-  python3.11 \
-  git \
-  cmake \
-  sudo \
-  gdb \
-  llvm-15-tools \
-  llvm-15-dev \
-  libedit-dev \
-  libssl-dev \
-  pkg-config \
-  zlib1g-dev \
-  xz-utils \
-  nodejs \
-  mingw-w64 \
-  libgccjit-12-dev \
-  && rm -rf /var/lib/apt/lists/*
-
-# Install powershell (universal package) so we can test x.ps1 on Linux
-RUN curl -sL "https://github.com/PowerShell/PowerShell/releases/download/v7.3.1/powershell_7.3.1-1.deb_amd64.deb" > powershell.deb && \
-    dpkg -i powershell.deb && \
-    rm -f powershell.deb
-
-COPY scripts/sccache.sh /scripts/
-RUN sh /scripts/sccache.sh
-
-# Make `libgccjit.so` accessible to the linker.
-RUN ln -s /usr/lib/gcc/x86_64-linux-gnu/12/libgccjit.so /usr/lib/x86_64-linux-gnu/libgccjit.so
-
-# We are disabling CI LLVM since this builder is intentionally using a host
-# LLVM, rather than the typical src/llvm-project LLVM.
-ENV NO_DOWNLOAD_CI_LLVM 1
-
-# This is not the latest LLVM version, so some components required by tests may
-# be missing.
-ENV IS_NOT_LATEST_LLVM 1
-
-# Using llvm-link-shared due to libffi issues -- see #34486
-ENV RUST_CONFIGURE_ARGS \
-      --build=x86_64-unknown-linux-gnu \
-      --llvm-root=/usr/lib/llvm-15 \
-      --enable-llvm-link-shared \
-      $USE_NEW_MANGLING \
-      --set rust.thin-lto-import-instr-limit=10
-
-COPY host-x86_64/x86_64-gnu-llvm-15/script.sh /tmp/
-
-ENV SCRIPT /tmp/script.sh
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-16/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-16/Dockerfile
index c177e7387fc8c..4757c3e7329d7 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-16/Dockerfile
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-16/Dockerfile
@@ -49,6 +49,6 @@ ENV RUST_CONFIGURE_ARGS \
       --enable-llvm-link-shared \
       --set rust.thin-lto-import-instr-limit=10
 
-COPY host-x86_64/x86_64-gnu-llvm-15/script.sh /tmp/
+COPY host-x86_64/x86_64-gnu-llvm-16/script.sh /tmp/
 
 ENV SCRIPT /tmp/script.sh
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-15/script.sh b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-16/script.sh
similarity index 100%
rename from src/ci/docker/host-x86_64/x86_64-gnu-llvm-15/script.sh
rename to src/ci/docker/host-x86_64/x86_64-gnu-llvm-16/script.sh
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-17/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-17/Dockerfile
index 76846f1fed7f3..dc5a04d4e06a7 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-17/Dockerfile
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-17/Dockerfile
@@ -45,6 +45,6 @@ ENV RUST_CONFIGURE_ARGS \
       --enable-llvm-link-shared \
       --set rust.thin-lto-import-instr-limit=10
 
-COPY host-x86_64/x86_64-gnu-llvm-15/script.sh /tmp/
+COPY host-x86_64/x86_64-gnu-llvm-16/script.sh /tmp/
 
 ENV SCRIPT /tmp/script.sh
diff --git a/src/ci/github-actions/ci.yml b/src/ci/github-actions/ci.yml
index da29ffb8e5f9b..5b9c90273a34c 100644
--- a/src/ci/github-actions/ci.yml
+++ b/src/ci/github-actions/ci.yml
@@ -334,7 +334,7 @@ jobs:
           - name: mingw-check-tidy
             <<: *job-linux-4c
 
-          - name: x86_64-gnu-llvm-15
+          - name: x86_64-gnu-llvm-16
             env:
               ENABLE_GCC_CODEGEN: "1"
             <<: *job-linux-16c
@@ -486,11 +486,6 @@ jobs:
               RUST_BACKTRACE: 1
             <<: *job-linux-8c
 
-          - name: x86_64-gnu-llvm-15
-            env:
-              RUST_BACKTRACE: 1
-            <<: *job-linux-8c
-
           - name: x86_64-gnu-nopt
             <<: *job-linux-4c
 
diff --git a/tests/assembly/asm/loongarch-type.rs b/tests/assembly/asm/loongarch-type.rs
index 4e296f3ade58b..4aeecf92d8659 100644
--- a/tests/assembly/asm/loongarch-type.rs
+++ b/tests/assembly/asm/loongarch-type.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 16.0
 // assembly-output: emit-asm
 // compile-flags: --target loongarch64-unknown-linux-gnu
 // needs-llvm-components: loongarch
@@ -42,7 +41,7 @@ extern "C" {
 
 // Hack to avoid function merging
 extern "Rust" {
-   fn dont_merge(s: &str);
+    fn dont_merge(s: &str);
 }
 
 // CHECK-LABEL: sym_fn:
diff --git a/tests/assembly/x86-stack-probes.rs b/tests/assembly/x86-stack-probes.rs
index c7141fb208a0d..64a4efc0e1881 100644
--- a/tests/assembly/x86-stack-probes.rs
+++ b/tests/assembly/x86-stack-probes.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 16
 // revisions: x86_64 i686
 // assembly-output: emit-asm
 //[x86_64] compile-flags: --target x86_64-unknown-linux-gnu
diff --git a/tests/codegen/issues/issue-101048.rs b/tests/codegen/issues/issue-101048.rs
index efa4db93ec212..e4712cf9cb3f6 100644
--- a/tests/codegen/issues/issue-101048.rs
+++ b/tests/codegen/issues/issue-101048.rs
@@ -1,5 +1,4 @@
 // compile-flags: -O
-// min-llvm-version: 16
 
 #![crate_type = "lib"]
 
diff --git a/tests/codegen/issues/issue-101082.rs b/tests/codegen/issues/issue-101082.rs
index 2cbe99942cba3..58fcd75a8f2de 100644
--- a/tests/codegen/issues/issue-101082.rs
+++ b/tests/codegen/issues/issue-101082.rs
@@ -1,5 +1,4 @@
 // compile-flags: -O
-// min-llvm-version: 16
 // ignore-debug: the debug assertions get in the way
 
 #![crate_type = "lib"]
diff --git a/tests/codegen/issues/issue-101814.rs b/tests/codegen/issues/issue-101814.rs
index 13796352c0285..63a8cebcb608a 100644
--- a/tests/codegen/issues/issue-101814.rs
+++ b/tests/codegen/issues/issue-101814.rs
@@ -1,5 +1,4 @@
 // compile-flags: -O
-// min-llvm-version: 16
 // ignore-debug: the debug assertions get in the way
 
 #![crate_type = "lib"]
diff --git a/tests/codegen/issues/issue-103132.rs b/tests/codegen/issues/issue-103132.rs
index cc87d7cd2b9da..521d424c2696b 100644
--- a/tests/codegen/issues/issue-103132.rs
+++ b/tests/codegen/issues/issue-103132.rs
@@ -1,5 +1,4 @@
 // compile-flags: -O -C overflow-checks
-// min-llvm-version: 16
 
 #![crate_type = "lib"]
 
diff --git a/tests/codegen/issues/issue-103327.rs b/tests/codegen/issues/issue-103327.rs
index cee00faccc811..021f1ca0c3af0 100644
--- a/tests/codegen/issues/issue-103327.rs
+++ b/tests/codegen/issues/issue-103327.rs
@@ -1,5 +1,4 @@
 // compile-flags: -O
-// min-llvm-version: 16
 
 #![crate_type = "lib"]
 
diff --git a/tests/codegen/issues/issue-103840.rs b/tests/codegen/issues/issue-103840.rs
index da64692d27d92..f19d7031bb386 100644
--- a/tests/codegen/issues/issue-103840.rs
+++ b/tests/codegen/issues/issue-103840.rs
@@ -1,5 +1,4 @@
 // compile-flags: -O
-// min-llvm-version: 16.0
 #![crate_type = "lib"]
 
 pub fn foo(t: &mut Vec<usize>) {
diff --git a/tests/codegen/issues/issue-75978.rs b/tests/codegen/issues/issue-75978.rs
index f335e92c3dc44..abfafc35f0b47 100644
--- a/tests/codegen/issues/issue-75978.rs
+++ b/tests/codegen/issues/issue-75978.rs
@@ -1,5 +1,4 @@
 // compile-flags: -O
-// min-llvm-version: 16
 
 #![crate_type = "lib"]
 
diff --git a/tests/codegen/issues/issue-99960.rs b/tests/codegen/issues/issue-99960.rs
index e9c9367fa64b6..ad0315a8227ec 100644
--- a/tests/codegen/issues/issue-99960.rs
+++ b/tests/codegen/issues/issue-99960.rs
@@ -1,5 +1,4 @@
 // compile-flags: -O
-// min-llvm-version: 16
 
 #![crate_type = "lib"]
 
diff --git a/tests/codegen/sanitizer/kasan-emits-instrumentation.rs b/tests/codegen/sanitizer/kasan-emits-instrumentation.rs
index 29d50d8df24ae..18d315c9598bf 100644
--- a/tests/codegen/sanitizer/kasan-emits-instrumentation.rs
+++ b/tests/codegen/sanitizer/kasan-emits-instrumentation.rs
@@ -6,10 +6,8 @@
 //[aarch64] needs-llvm-components: aarch64
 //[riscv64imac] compile-flags: --target riscv64imac-unknown-none-elf
 //[riscv64imac] needs-llvm-components: riscv
-//[riscv64imac] min-llvm-version: 16
 //[riscv64gc] compile-flags: --target riscv64gc-unknown-none-elf
 //[riscv64gc] needs-llvm-components: riscv
-//[riscv64gc] min-llvm-version: 16
 //[x86_64] compile-flags: --target x86_64-unknown-none
 //[x86_64] needs-llvm-components: x86
 
diff --git a/tests/codegen/slice-iter-fold.rs b/tests/codegen/slice-iter-fold.rs
index 9391c176130a4..a55425cb6bbc6 100644
--- a/tests/codegen/slice-iter-fold.rs
+++ b/tests/codegen/slice-iter-fold.rs
@@ -1,6 +1,5 @@
 // ignore-debug: the debug assertions get in the way
 // compile-flags: -O
-// min-llvm-version: 16
 #![crate_type = "lib"]
 
 // CHECK-LABEL: @slice_fold_to_last
diff --git a/tests/codegen/stack-probes-call.rs b/tests/codegen/stack-probes-call.rs
deleted file mode 100644
index a18fd41c28c0e..0000000000000
--- a/tests/codegen/stack-probes-call.rs
+++ /dev/null
@@ -1,24 +0,0 @@
-// Check the "probe-stack" attribute for targets with `StackProbeType::Call`,
-// or `StackProbeType::InlineOrCall` when running on older LLVM.
-
-// compile-flags: -C no-prepopulate-passes
-// revisions: i686 x86_64
-//[i686] compile-flags: --target i686-unknown-linux-gnu
-//[i686] needs-llvm-components: x86
-//[i686] ignore-llvm-version: 16 - 99
-//[x86_64] compile-flags: --target x86_64-unknown-linux-gnu
-//[x86_64] needs-llvm-components: x86
-//[x86_64] ignore-llvm-version: 16 - 99
-
-#![crate_type = "rlib"]
-#![feature(no_core, lang_items)]
-#![no_core]
-
-#[lang = "sized"]
-trait Sized {}
-
-#[no_mangle]
-pub fn foo() {
-// CHECK: @foo() unnamed_addr #0
-// CHECK: attributes #0 = { {{.*}}"probe-stack"="__rust_probestack"{{.*}} }
-}
diff --git a/tests/codegen/stack-probes-inline.rs b/tests/codegen/stack-probes-inline.rs
index a6b781de531fd..058c363969f08 100644
--- a/tests/codegen/stack-probes-inline.rs
+++ b/tests/codegen/stack-probes-inline.rs
@@ -13,10 +13,8 @@
 //[s390x] needs-llvm-components: systemz
 //[i686] compile-flags: --target i686-unknown-linux-gnu
 //[i686] needs-llvm-components: x86
-//[i686] min-llvm-version: 16
 //[x86_64] compile-flags: --target x86_64-unknown-linux-gnu
 //[x86_64] needs-llvm-components: x86
-//[x86_64] min-llvm-version: 16
 
 #![crate_type = "rlib"]
 #![feature(no_core, lang_items)]
diff --git a/tests/codegen/vec-in-place.rs b/tests/codegen/vec-in-place.rs
index d68067ceb19f7..5cf7add836dfb 100644
--- a/tests/codegen/vec-in-place.rs
+++ b/tests/codegen/vec-in-place.rs
@@ -1,6 +1,5 @@
 // ignore-debug: the debug assertions get in the way
 // compile-flags: -O -Z merge-functions=disabled
-// min-llvm-version: 16
 #![crate_type = "lib"]
 
 // Ensure that trivial casts of vec elements are O(1)
diff --git a/tests/run-make/compressed-debuginfo/Makefile b/tests/run-make/compressed-debuginfo/Makefile
index f9e4927d008e4..d2f24dde00d7b 100644
--- a/tests/run-make/compressed-debuginfo/Makefile
+++ b/tests/run-make/compressed-debuginfo/Makefile
@@ -2,7 +2,6 @@
 include ../tools.mk
 
 # only-linux
-# min-llvm-version: 16.0
 #
 # This tests debuginfo-compression.
 
diff --git a/tests/ui/const_prop/apfloat-f64-roundtrip.rs b/tests/ui/const_prop/apfloat-f64-roundtrip.rs
index 9fb2ac96bebdb..5f3ec931c82c6 100644
--- a/tests/ui/const_prop/apfloat-f64-roundtrip.rs
+++ b/tests/ui/const_prop/apfloat-f64-roundtrip.rs
@@ -1,6 +1,5 @@
 // run-pass
 // compile-flags: -O -Zmir-opt-level=3 -Cno-prepopulate-passes
-// min-llvm-version: 16.0 (requires APFloat fixes in LLVM)
 
 // Regression test for a broken MIR optimization (issue #113407).
 pub fn main() {
diff --git a/tests/ui/numbers-arithmetic/issue-105626.rs b/tests/ui/numbers-arithmetic/issue-105626.rs
index f97edd510c9e6..5466f8e18d472 100644
--- a/tests/ui/numbers-arithmetic/issue-105626.rs
+++ b/tests/ui/numbers-arithmetic/issue-105626.rs
@@ -1,6 +1,5 @@
 // run-pass
 // only-x86
-// min-system-llvm-version: 16
 // compile-flags: -Ctarget-feature=+sse2
 
 use std::hint::black_box;
diff --git a/tests/ui/sanitize/cfg-kasan.rs b/tests/ui/sanitize/cfg-kasan.rs
index d721011f3ee51..fb9a6f549ce0c 100644
--- a/tests/ui/sanitize/cfg-kasan.rs
+++ b/tests/ui/sanitize/cfg-kasan.rs
@@ -8,10 +8,8 @@
 //[aarch64] needs-llvm-components: aarch64
 //[riscv64imac] compile-flags: --target riscv64imac-unknown-none-elf
 //[riscv64imac] needs-llvm-components: riscv
-//[riscv64imac] min-llvm-version: 16
 //[riscv64gc] compile-flags: --target riscv64gc-unknown-none-elf
 //[riscv64gc] needs-llvm-components: riscv
-//[riscv64gc] min-llvm-version: 16
 //[x86_64] compile-flags: --target x86_64-unknown-none
 //[x86_64] needs-llvm-components: x86