diff --git a/test/ClangImporter/pch-bridging-header-unittest-ok.swift b/test/ClangImporter/pch-bridging-header-unittest-ok.swift
index d68ff4322af6b..c0d6f5c352223 100644
--- a/test/ClangImporter/pch-bridging-header-unittest-ok.swift
+++ b/test/ClangImporter/pch-bridging-header-unittest-ok.swift
@@ -1,7 +1,7 @@
 // REQUIRES: objc_interop
 // RUN: %empty-directory(%t)
 // RUN: mkdir -p %t/tmp
-// RUN: %target-swiftc_driver -emit-module -import-objc-header %S/Inputs/app-bridging-header-to-pch.h -module-name App -emit-module-path %t/App.swiftmodule %S/Inputs/app-that-uses-pch-bridging-header.swift
+// RUN: %target-swiftc_driver -emit-module -disable-bridging-pch -import-objc-header %S/Inputs/app-bridging-header-to-pch.h -module-name App -emit-module-path %t/App.swiftmodule %S/Inputs/app-that-uses-pch-bridging-header.swift
 // RUN: llvm-bcanalyzer -dump %t/App.swiftmodule | %FileCheck %s
 // CHECK: IMPORTED_HEADER{{.*}}Inputs/app-bridging-header-to-pch.h
 
diff --git a/test/ClangImporter/pch-bridging-header-unittest-warn.swift b/test/ClangImporter/pch-bridging-header-unittest-warn.swift
index f630c30328238..00d281129ca3b 100644
--- a/test/ClangImporter/pch-bridging-header-unittest-warn.swift
+++ b/test/ClangImporter/pch-bridging-header-unittest-warn.swift
@@ -1,7 +1,7 @@
 // REQUIRES: objc_interop
 // RUN: %empty-directory(%t)
 // RUN: mkdir -p %t/tmp
-// RUN: %target-swiftc_driver -emit-module -import-objc-header %S/Inputs/app-bridging-header-to-pch.h -module-name App -emit-module-path %t/App.swiftmodule %S/Inputs/app-that-uses-pch-bridging-header.swift
+// RUN: %target-swiftc_driver -emit-module -disable-bridging-pch -import-objc-header %S/Inputs/app-bridging-header-to-pch.h -module-name App -emit-module-path %t/App.swiftmodule %S/Inputs/app-that-uses-pch-bridging-header.swift
 // RUN: llvm-bcanalyzer -dump %t/App.swiftmodule | %FileCheck %s
 // CHECK: IMPORTED_HEADER{{.*}}Inputs/app-bridging-header-to-pch.h
 
diff --git a/test/ClangImporter/pch-bridging-header-with-another-bridging-header.swift b/test/ClangImporter/pch-bridging-header-with-another-bridging-header.swift
index 63d232667208f..f66c3e9436d4b 100644
--- a/test/ClangImporter/pch-bridging-header-with-another-bridging-header.swift
+++ b/test/ClangImporter/pch-bridging-header-with-another-bridging-header.swift
@@ -1,5 +1,5 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-build-swift -emit-module -import-objc-header %S/Inputs/pch-bridging-header-with-another-bridging-header/app.h -I %S/Inputs/pch-bridging-header-with-another-bridging-header -module-name App -emit-module-path %t/App.swiftmodule %S/../Inputs/empty.swift
+// RUN: %target-build-swift -emit-module -disable-bridging-pch -import-objc-header %S/Inputs/pch-bridging-header-with-another-bridging-header/app.h -I %S/Inputs/pch-bridging-header-with-another-bridging-header -module-name App -emit-module-path %t/App.swiftmodule %S/../Inputs/empty.swift
 // RUN: llvm-bcanalyzer -dump %t/App.swiftmodule | %FileCheck %s
 
 // CHECK: IMPORTED_HEADER{{.*}}Inputs/pch-bridging-header-with-another-bridging-header/app.h
@@ -18,4 +18,4 @@
 
 import App
 
-_ = app_function(2)
\ No newline at end of file
+_ = app_function(2)
diff --git a/test/ClangImporter/pch-bridging-header.swift b/test/ClangImporter/pch-bridging-header.swift
index 851e069f0041d..2371547337cd3 100644
--- a/test/ClangImporter/pch-bridging-header.swift
+++ b/test/ClangImporter/pch-bridging-header.swift
@@ -7,11 +7,13 @@
 // RUN: %target-typecheck-verify-swift -import-objc-header %t/sdk-bridging-header.pch
 
 // Now test the driver-automated version is inert when disabled
-// RUN: env TMPDIR=%t/tmp/ %target-swiftc_driver -typecheck -disable-bridging-pch -save-temps %s -import-objc-header %S/Inputs/sdk-bridging-header.h
+// Output path of the PCH differs in the new driver, so force SWIFT_USE_OLD_DRIVER for now.
+// RUN: env TMPDIR=%t/tmp/ SWIFT_USE_OLD_DRIVER=1 %target-swiftc_driver -typecheck -disable-bridging-pch -save-temps %s -import-objc-header %S/Inputs/sdk-bridging-header.h
 // RUN: not ls %t/tmp/*.pch >/dev/null 2>&1
 
 // Test the driver-automated version works by default
-// RUN: env TMPDIR=%t/tmp/ %target-swiftc_driver -typecheck -save-temps %s -import-objc-header %S/Inputs/sdk-bridging-header.h
+// Output path of the PCH differs in the new driver, so force SWIFT_USE_OLD_DRIVER for now.
+// RUN: env TMPDIR=%t/tmp/ SWIFT_USE_OLD_DRIVER=1 %target-swiftc_driver -typecheck -save-temps %s -import-objc-header %S/Inputs/sdk-bridging-header.h
 // RUN: ls %t/tmp/*.pch >/dev/null 2>&1
 // RUN: llvm-objdump --raw-clang-ast %t/tmp/*.pch | llvm-bcanalyzer -dump | %FileCheck %s
 // CHECK: ORIGINAL_FILE{{.*}}Inputs/sdk-bridging-header.h
diff --git a/test/DebugInfo/ASTSection_ObjC.swift b/test/DebugInfo/ASTSection_ObjC.swift
index 872c114f06ad7..6acb79357a66e 100644
--- a/test/DebugInfo/ASTSection_ObjC.swift
+++ b/test/DebugInfo/ASTSection_ObjC.swift
@@ -4,7 +4,7 @@
 // RUN: %empty-directory(%t)
 
 // RUN: cp %S/Inputs/serialized-objc-header.h %t
-// RUN: %target-build-swift -emit-executable %S/ASTSection.swift -g -o %t/ASTSection-with-ObjC -import-objc-header %t/serialized-objc-header.h -DOBJC -module-name ASTSection -emit-module
+// RUN: %target-build-swift -disable-bridging-pch -emit-executable %S/ASTSection.swift -g -o %t/ASTSection-with-ObjC -import-objc-header %t/serialized-objc-header.h -DOBJC -module-name ASTSection -emit-module
 // RUN: %lldb-moduleimport-test -verbose %t/ASTSection-with-ObjC | %FileCheck %s
 
 // RUN: rm %t/serialized-objc-header.h
diff --git a/test/DebugInfo/file_compilation_dir.swift b/test/DebugInfo/file_compilation_dir.swift
index 8d029751ad0b1..d0c8e93ab24a3 100644
--- a/test/DebugInfo/file_compilation_dir.swift
+++ b/test/DebugInfo/file_compilation_dir.swift
@@ -6,10 +6,11 @@
 // RUN: mkdir -p %t
 // RUN: cd %t
 // RUN: cp %s .
-// RUN: %target-swiftc_driver -g \
+// Output paths differ in the new driver, so force SWIFT_USE_OLD_DRIVER for now.
+// RUN: env SWIFT_USE_OLD_DRIVER=1 %target-swiftc_driver -g \
 // RUN:   -c -file-compilation-dir /path/to \
 // RUN:   file_compilation_dir.swift -o - -emit-ir | %FileCheck --check-prefix=CHECK-REL %s
-// RUN: %target-swiftc_driver -g \
+// RUN: env SWIFT_USE_OLD_DRIVER=1 %target-swiftc_driver -g \
 // RUN:   -c -file-compilation-dir . \
 // RUN:   file_compilation_dir.swift -o - -emit-ir | %FileCheck --check-prefix=CHECK-REL-CWD %s
 
diff --git a/test/IDE/local_types.swift b/test/IDE/local_types.swift
index baa0a4687a2ea..e957ee0d88ee2 100644
--- a/test/IDE/local_types.swift
+++ b/test/IDE/local_types.swift
@@ -1,7 +1,10 @@
 // Tests lookup and mangling of local types
 
+// Avoid emitting the module separately since that would skip non-inlinable
+// function bodies without types, and we want to print the decls in
+// `singleDefaultArgument`.
 // RUN: %empty-directory(%t)
-// RUN: %target-swiftc_driver -v -emit-module -module-name LocalTypes -o %t/LocalTypes.swiftmodule %s
+// RUN: %target-swiftc_driver -v -no-emit-module-separately -emit-module -module-name LocalTypes -o %t/LocalTypes.swiftmodule %s
 // RUN: %target-swift-ide-test -print-local-types -I %t -module-to-print LocalTypes -source-filename %s > %t.dump
 // RUN: %FileCheck %s < %t.dump
 // RUN: %FileCheck -check-prefix=NEGATIVE %s < %t.dump
diff --git a/test/IDE/merge_local_types.swift b/test/IDE/merge_local_types.swift
index c5cb75e5d7774..973f6fc125b3e 100644
--- a/test/IDE/merge_local_types.swift
+++ b/test/IDE/merge_local_types.swift
@@ -3,7 +3,7 @@
 // RUN: %empty-directory(%t)
 
 // Create separate modules and merge them together
-// RUN: %target-swiftc_driver -v -emit-module -module-name LocalTypesMerged -o %t/LocalTypesMerged.swiftmodule %s %S/local_types.swift
+// RUN: %target-swiftc_driver -v -no-emit-module-separately -emit-module -module-name LocalTypesMerged -o %t/LocalTypesMerged.swiftmodule %s %S/local_types.swift
 
 // RUN: %target-swift-ide-test -print-local-types -I %t -module-to-print LocalTypesMerged -source-filename %s | %FileCheck %s -allow-deprecated-dag-overlap
 
diff --git a/test/Index/Store/driver-index-with-auxiliary-outputs.swift b/test/Index/Store/driver-index-with-auxiliary-outputs.swift
deleted file mode 100644
index 3979097671928..0000000000000
--- a/test/Index/Store/driver-index-with-auxiliary-outputs.swift
+++ /dev/null
@@ -1,35 +0,0 @@
-// RUN: %empty-directory(%t)
-
-// This test is very deliberately *not* indexing the current file; we need to
-// make sure the frontend job doesn't try to emit the auxiliary outputs based
-// on the non-indexed files. (This is how Xcode currently constructs -index-file
-// invocations: take a normal build command and add extra arguments to it.)
-// RUN: %target-build-swift -index-file -index-file-path %S/Inputs/SwiftModuleA.swift %S/Inputs/SwiftModuleA.swift %s -index-store-path %t/idx -Xfrontend -index-ignore-stdlib -module-name driver_index -emit-objc-header-path %t/out.h -emit-module-interface-path %t/out.swiftinterface
-
-// RUN: test ! -f %t/out.h
-// RUN: test ! -f %t/out.swiftinterface
-// RUN: c-index-test core -print-unit %t/idx | %FileCheck %s
-
-// CHECK-LABEL: module-name: driver_index
-// CHECK: DEPEND START
-// CHECK-NOT: Record |
-// CHECK: Record | user | {{.+}}SwiftModuleA.swift
-// CHECK-NOT: Record |
-// CHECK: DEPEND END
-
-#if _runtime(_ObjC)
-
-// Do a stronger test here involving checking @objc
-import ObjectiveC
-
-public class PossiblyObjC: NSObject {
-  @objc public init(x: Int) {}
-}
-
-#else // _runtime(_ObjC)
-
-public class Boring {
-  init()
-}
-
-#endif // _runtime(_ObjC)
diff --git a/test/Misc/stats_dir_failure_count.swift b/test/Misc/stats_dir_failure_count.swift
index d771991301fac..7e678cbd1476f 100644
--- a/test/Misc/stats_dir_failure_count.swift
+++ b/test/Misc/stats_dir_failure_count.swift
@@ -1,7 +1,7 @@
 // Check that a failed process-tree emits nonzero failure counters
 // RUN: %empty-directory(%t)
 // RUN: echo zzz >%t/other.swift
-// RUN: not %target-swiftc_driver -continue-building-after-errors -D BROKEN -j 2 -typecheck -stats-output-dir %t %s %t/other.swift
+// RUN: not env SWIFT_USE_OLD_DRIVER=1 %target-swiftc_driver -continue-building-after-errors -D BROKEN -j 2 -typecheck -stats-output-dir %t %s %t/other.swift
 // RUN: %{python} %utils/process-stats-dir.py --set-csv-baseline %t/stats.csv %t
 // RUN: %FileCheck -input-file %t/stats.csv -check-prefix=FAILURE %s
 // FAILURE: {{"Driver.NumProcessFailures"	1$}}
diff --git a/test/Misc/stats_dir_plausible_maxrss.swift b/test/Misc/stats_dir_plausible_maxrss.swift
index a579a8eb26600..362407d2148c4 100644
--- a/test/Misc/stats_dir_plausible_maxrss.swift
+++ b/test/Misc/stats_dir_plausible_maxrss.swift
@@ -1,6 +1,6 @@
 // RUN: %empty-directory(%t)
 // RUN: touch %t/main.swift
-// RUN: %target-swiftc_driver -o %t/main -module-name main -stats-output-dir %t %t/main.swift
+// RUN: env SWIFT_USE_OLD_DRIVER=1 %target-swiftc_driver -o %t/main -module-name main -stats-output-dir %t %t/main.swift
 // RUN: %{python} %utils/process-stats-dir.py --set-csv-baseline %t/frontend.csv %t
 // RUN: %FileCheck -input-file %t/frontend.csv %s
 
diff --git a/test/ModuleInterface/convenience-init.swift b/test/ModuleInterface/convenience-init.swift
index 2a8aee408be7b..0a136d9c221d1 100644
--- a/test/ModuleInterface/convenience-init.swift
+++ b/test/ModuleInterface/convenience-init.swift
@@ -1,7 +1,7 @@
 // RUN: %empty-directory(%t)
 
 // Generate the parseable interface of the current file via the merge-modules step
-// RUN: %target-build-swift -emit-module -o %t/Test.swiftmodule -emit-module-interface-path %t/TestMerge.swiftinterface -module-name Test %s
+// RUN: %target-build-swift -no-emit-module-separately -emit-module -o %t/Test.swiftmodule -emit-module-interface-path %t/TestMerge.swiftinterface -module-name Test %s
 
 // Generate the parseable interface of the current file via a single frontend invocation
 // RUN: %target-swift-frontend -typecheck  -enable-objc-interop -emit-module-interface-path %t/TestSingle.swiftinterface -module-name Test %s
diff --git a/test/ModuleInterface/enums-layout.swift b/test/ModuleInterface/enums-layout.swift
index 7bf5423d9b5b1..a1c15b189677b 100644
--- a/test/ModuleInterface/enums-layout.swift
+++ b/test/ModuleInterface/enums-layout.swift
@@ -1,5 +1,5 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-build-swift -emit-module-interface-path %t/Lib.swiftinterface -emit-module -o %t/unused.swiftmodule -enable-library-evolution -Xfrontend -enable-objc-interop -Xfrontend -disable-objc-attr-requires-foundation-module -swift-version 5 %S/Inputs/enums-layout-helper.swift -module-name Lib
+// RUN: %target-build-swift -no-emit-module-separately -emit-module-interface-path %t/Lib.swiftinterface -emit-module -o %t/unused.swiftmodule -enable-library-evolution -Xfrontend -enable-objc-interop -Xfrontend -disable-objc-attr-requires-foundation-module -swift-version 5 %S/Inputs/enums-layout-helper.swift -module-name Lib
 // RUN: %FileCheck -check-prefix CHECK -check-prefix CHECK-MULTI-FILE %S/Inputs/enums-layout-helper.swift < %t/Lib.swiftinterface
 // RUN: %target-swift-frontend -enable-objc-interop -compile-module-from-interface %t/Lib.swiftinterface -o  %t/compiled-from-interface.swiftmodule -module-name Lib
 // RUN: %target-swift-frontend -enable-objc-interop -O -emit-ir -primary-file %s -I %t -Xllvm -swiftmergefunc-threshold=0 | %FileCheck %s
diff --git a/test/ModuleInterface/print_package_name_in_non_package_interface.swift b/test/ModuleInterface/print_package_name_in_non_package_interface.swift
index b743b9f3177e2..511b44ba0a94a 100644
--- a/test/ModuleInterface/print_package_name_in_non_package_interface.swift
+++ b/test/ModuleInterface/print_package_name_in_non_package_interface.swift
@@ -51,7 +51,10 @@
 // RUN: rm -rf %t/Bar.package.swiftinterface
 
 /// Print -package-name in public or private interface.
-// RUN: %target-build-swift -emit-module %t/Bar.swift -I %t \
+/// Note the order of arguments differs across old/new driver, so force old
+/// driver for now.
+// RUN: env SWIFT_USE_OLD_DRIVER=1 %target-build-swift \
+// RUN:   -emit-module %t/Bar.swift -I %t \
 // RUN:   -module-name Bar -package-name barpkg \
 // RUN:   -enable-library-evolution -swift-version 6 \
 // RUN:   -Xfrontend -print-package-name-in-non-package-interface \
diff --git a/test/SILOptimizer/cmo-with-package-decls.swift b/test/SILOptimizer/cmo-with-package-decls.swift
index 259025678ee67..48d5a3f2225fa 100644
--- a/test/SILOptimizer/cmo-with-package-decls.swift
+++ b/test/SILOptimizer/cmo-with-package-decls.swift
@@ -3,7 +3,7 @@
 // RUN: %target-build-swift -O -wmo -Xfrontend -enable-default-cmo -parse-as-library -emit-module -emit-module-path=%t/Module.swiftmodule -module-name=Module -package-name Pkg -I%t -I%S/Inputs/cross-module %S/Inputs/cross-module/default-module.swift -c -o %t/module.o
 // RUN: %target-build-swift -O -wmo -Xfrontend -enable-default-cmo -parse-as-library -emit-tbd -emit-tbd-path %t/ModuleTBD.tbd -emit-module -emit-module-path=%t/ModuleTBD.swiftmodule -module-name=ModuleTBD -package-name Pkg -I%t -I%S/Inputs/cross-module %S/Inputs/cross-module/default-module.swift -c -o %t/moduletbd.o -Xfrontend -tbd-install_name -Xfrontend module
 
-// RUN: %target-build-swift -O -wmo -module-name=Main -package-name Pkg -I%t -I%S/Inputs/cross-module %s -emit-sil -o %t/Main.sil
+// RUN: %target-build-swift -Xfrontend -enable-default-cmo -O -wmo -module-name=Main -package-name Pkg -I%t -I%S/Inputs/cross-module %s -emit-sil -o %t/Main.sil
 // RUN: %FileCheck %s < %t/Main.sil
 
 // REQUIRES: swift_in_compiler
@@ -12,7 +12,7 @@ import Module
 import ModuleTBD
 
 // static ModuleStruct.privateFunctionPointer
-// CHECK-LABEL: sil_global public_external @$s6Module0A6StructV22privateFunctionPointeryS2icvpZ : $@callee_guaranteed (Int) -> Int{{$}}
+// CHECK-LABEL: sil_global public_external [serialized] @$s6Module0A6StructV22privateFunctionPointeryS2icvpZ : $@callee_guaranteed (Int) -> Int{{$}}
 
 // static ModuleStruct.publicFunctionPointer
 // CHECK-LABEL: sil_global public_external [serialized] @$s6Module0A6StructV21publicFunctionPointeryS2icvpZ : $@callee_guaranteed (Int) -> Int
diff --git a/test/SILOptimizer/default-cmo.swift b/test/SILOptimizer/default-cmo.swift
index d97b656209f24..0e9099b0f06f3 100644
--- a/test/SILOptimizer/default-cmo.swift
+++ b/test/SILOptimizer/default-cmo.swift
@@ -5,14 +5,14 @@
 // RUN: %target-build-swift -O -wmo -Xfrontend -enable-default-cmo -parse-as-library -emit-module -emit-module-path=%t/Module.swiftmodule -module-name=Module -package-name Pkg -I%t -I%S/Inputs/cross-module %S/Inputs/cross-module/default-module.swift -c -o %t/module.o
 // RUN: %target-build-swift -O -wmo -Xfrontend -enable-default-cmo -parse-as-library -emit-tbd -emit-tbd-path %t/ModuleTBD.tbd -emit-module -emit-module-path=%t/ModuleTBD.swiftmodule -module-name=ModuleTBD -package-name Pkg -I%t -I%S/Inputs/cross-module %S/Inputs/cross-module/default-module.swift -c -o %t/moduletbd.o -Xfrontend -tbd-install_name -Xfrontend module
 
-// RUN: %target-build-swift -O -wmo -module-name=Main -package-name Pkg -I%t -I%S/Inputs/cross-module %s -emit-sil | %FileCheck %s
+// RUN: %target-build-swift -Xfrontend -enable-default-cmo -O -wmo -module-name=Main -package-name Pkg -I%t -I%S/Inputs/cross-module %s -emit-sil | %FileCheck %s
 
 // REQUIRES: swift_in_compiler
 
 import Module
 import ModuleTBD
 
-// CHECK-LABEL: sil_global public_external @$s6Module0A6StructV22privateFunctionPointeryS2icvpZ : $@callee_guaranteed (Int) -> Int{{$}}
+// CHECK-LABEL: sil_global public_external [serialized] @$s6Module0A6StructV22privateFunctionPointeryS2icvpZ : $@callee_guaranteed (Int) -> Int{{$}}
 
 public func callPublicFunctionPointer(_ x: Int) -> Int {
   return Module.ModuleStruct.publicFunctionPointer(x)
diff --git a/test/Serialization/search-paths-relative.swift b/test/Serialization/search-paths-relative.swift
index 1b673196fb493..398562d1b2d34 100644
--- a/test/Serialization/search-paths-relative.swift
+++ b/test/Serialization/search-paths-relative.swift
@@ -4,7 +4,8 @@
 // RUN: %empty-directory(%t/Frameworks/has_alias.framework/Modules/has_alias.swiftmodule)
 // RUN: %target-swift-frontend -emit-module -o %t/Frameworks/has_alias.framework/Modules/has_alias.swiftmodule/%target-swiftmodule-name %S/Inputs/alias.swift -module-name has_alias
 
-// RUN: cd %t/secret && %target-swiftc_driver -emit-module -o %t/has_xref.swiftmodule -I . -F ../Frameworks -parse-as-library %S/Inputs/has_xref.swift %S/../Inputs/empty.swift -Xfrontend -serialize-debugging-options -Xcc -ivfsoverlay -Xcc %S/../Inputs/unextended-module-overlay.yaml -Xcc -DDUMMY
+// Output paths differ in the new driver, so force SWIFT_USE_OLD_DRIVER for now.
+// RUN: cd %t/secret && env SWIFT_USE_OLD_DRIVER=1 %target-swiftc_driver -emit-module -o %t/has_xref.swiftmodule -I . -F ../Frameworks -parse-as-library %S/Inputs/has_xref.swift %S/../Inputs/empty.swift -Xfrontend -serialize-debugging-options -Xcc -ivfsoverlay -Xcc %S/../Inputs/unextended-module-overlay.yaml -Xcc -DDUMMY
 // RUN: %target-swift-frontend %s -typecheck -I %t
 
 // Ensure that in Swift 6 mode we do not read out search paths, thus are no longer able to
diff --git a/test/SourceKit/InterfaceGen/gen_module_group.swift b/test/SourceKit/InterfaceGen/gen_module_group.swift
index bffaaa4c26693..ee03cdd998ea4 100644
--- a/test/SourceKit/InterfaceGen/gen_module_group.swift
+++ b/test/SourceKit/InterfaceGen/gen_module_group.swift
@@ -6,7 +6,7 @@
 // FIXME: We don't currently handle group info for multi-file builds,
 // so just make sure we don't crash.
 // RUN: %empty-directory(%t.multifrontend)
-// RUN: %target-build-swift -module-name MyModule -emit-module -emit-module-path %t.multifrontend/MyModule.swiftmodule  -Xfrontend -group-info-path -Xfrontend %S/Inputs/group.json %S/Inputs/swift_mod.swift %S/Inputs/swift_mod_syn.swift
+// RUN: %target-build-swift -module-name MyModule -emit-module -emit-module-path %t.multifrontend/MyModule.swiftmodule -no-emit-module-separately -Xfrontend -group-info-path -Xfrontend %S/Inputs/group.json %S/Inputs/swift_mod.swift %S/Inputs/swift_mod_syn.swift
 // RUN: %sourcekitd-test -req=interface-gen -module MyModule -group-name A -- -I %t.multifrontend -target %target-triple | %FileCheck -check-prefix=EMPTY %s
 
 // GROUPA: MyClass
diff --git a/test/SymbolGraph/Symbols/Mixins/DeclarationFragments/Full/SomeProtocol.swift b/test/SymbolGraph/Symbols/Mixins/DeclarationFragments/Full/SomeProtocol.swift
index 9d1c723db6b8d..6c05f6eedc712 100644
--- a/test/SymbolGraph/Symbols/Mixins/DeclarationFragments/Full/SomeProtocol.swift
+++ b/test/SymbolGraph/Symbols/Mixins/DeclarationFragments/Full/SomeProtocol.swift
@@ -4,8 +4,12 @@
 // RUN: %FileCheck %s --input-file %t/SomeProtocol.symbols.json
 // RUN: %FileCheck %s --input-file %t/SomeProtocol.symbols.json --check-prefix MULTI
 
+// Note we use '-wmo' here to make sure the driver doesn't do merge-modules,
+// which would result in printing the Type instead of TypeRepr, leading to
+// inconsistency with the new driver. Once we switch to always using the new
+// driver, we can remove it.
 // RUN: %empty-directory(%t)
-// RUN: %target-build-swift %s -module-name SomeProtocol -emit-module -emit-module-path %t/SomeProtocol.swiftmodule -emit-symbol-graph -emit-symbol-graph-dir %t/
+// RUN: %target-build-swift %s -module-name SomeProtocol -emit-module -wmo -emit-module-path %t/SomeProtocol.swiftmodule -emit-symbol-graph -emit-symbol-graph-dir %t/
 // RUN: %validate-json %t/SomeProtocol.symbols.json %t/SomeProtocol.formatted.symbols.json
 // RUN: %FileCheck %s --input-file %t/SomeProtocol.formatted.symbols.json
 // RUN: %FileCheck %s --input-file %t/SomeProtocol.formatted.symbols.json --check-prefix MULTI
@@ -19,7 +23,7 @@ public func doSomething(with param: some SomeProtocol) {}
 
 public protocol OtherProtocol {}
 
-public func doSomethingElse(with param: some SomeProtocol & OtherProtocol) {}
+public func doSomethingElse(with param: some OtherProtocol & SomeProtocol) {}
 
 // CHECK-LABEL:        "precise": "s:12SomeProtocol11doSomething4withyx_tA2ARzlF",
 
diff --git a/test/TBD/output-path-deduction.swift b/test/TBD/output-path-deduction.swift
deleted file mode 100644
index c7bdf51a24896..0000000000000
--- a/test/TBD/output-path-deduction.swift
+++ /dev/null
@@ -1,13 +0,0 @@
-// REQUIRES: VENDOR=apple 
-// RUN: %empty-directory(%t)
-
-// RUN: cd %t; %target-build-swift -emit-module -emit-tbd %s -Xfrontend -tbd-install_name -Xfrontend test
-// RUN: test -e %t/main.tbd
-// RUN: %target-build-swift -emit-module -emit-tbd %s -o %t/default -Xfrontend -tbd-install_name -Xfrontend test
-// RUN: test -e %t/default.tbd
-// RUN: %target-build-swift -emit-module -emit-tbd %s -o %t/module_name -module-name module_name_different -Xfrontend -tbd-install_name -Xfrontend test
-// RUN: test -e %t/module_name.tbd
-// RUN: %target-build-swift -emit-module -emit-tbd-path %t/hard_to_guess_explicit_path.tbd %s -o %t/explicit_path -Xfrontend -tbd-install_name -Xfrontend test
-// RUN: test -e %t/hard_to_guess_explicit_path.tbd
-// RUN: %target-build-swift -emit-module -emit-tbd %s -emit-module-path %t/emit_module_path.swiftmodule -module-name emit_module_path_different -Xfrontend -tbd-install_name -Xfrontend test
-// RUN: test -e %t/emit_module_path.tbd
diff --git a/test/attr/open.swift b/test/attr/open.swift
index 862b89d487ad3..9a8fb1172f708 100644
--- a/test/attr/open.swift
+++ b/test/attr/open.swift
@@ -1,5 +1,5 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-build-swift -emit-module -c %S/Inputs/OpenHelpers.swift -o %t/OpenHelpers.swiftmodule
+// RUN: %target-build-swift -emit-module %S/Inputs/OpenHelpers.swift -o %t/OpenHelpers.swiftmodule
 // RUN: %target-typecheck-verify-swift -I %t
 
 import OpenHelpers
diff --git a/validation-test/Serialization/bridging-header-first.swift b/validation-test/Serialization/bridging-header-first.swift
index a05b57c65c3fa..6691c8e6c83f7 100644
--- a/validation-test/Serialization/bridging-header-first.swift
+++ b/validation-test/Serialization/bridging-header-first.swift
@@ -1,9 +1,9 @@
 // RUN: %empty-directory(%t)
 
-// RUN: %target-build-swift -emit-module -emit-executable %s -g -I %S/Inputs/bridging-header-first/ -import-objc-header %S/Inputs/bridging-header-first/bridging.h -o %t/main
+// RUN: %target-build-swift -emit-module -emit-executable %s -g -I %S/Inputs/bridging-header-first/ -disable-bridging-pch -import-objc-header %S/Inputs/bridging-header-first/bridging.h -o %t/main
 // RUN: llvm-bcanalyzer -dump %t/main.swiftmodule | %FileCheck -check-prefix CHECK-DUMP %s
 
-// RUN: %target-build-swift -emit-module -emit-executable %s -g -I %S/Inputs/bridging-header-first/ -import-objc-header %S/Inputs/bridging-header-first/bridging.h -o %t/main -whole-module-optimization
+// RUN: %target-build-swift -emit-module -emit-executable %s -g -I %S/Inputs/bridging-header-first/ -disable-bridging-pch -import-objc-header %S/Inputs/bridging-header-first/bridging.h -o %t/main -whole-module-optimization
 // RUN: llvm-bcanalyzer -dump %t/main.swiftmodule | %FileCheck -check-prefix CHECK-DUMP %s
 
 // REQUIRES: objc_interop
diff --git a/validation-test/Serialization/rdar29694978.swift b/validation-test/Serialization/rdar29694978.swift
index 50a74e71502ef..831f312553a7b 100644
--- a/validation-test/Serialization/rdar29694978.swift
+++ b/validation-test/Serialization/rdar29694978.swift
@@ -1,5 +1,6 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-build-swift %s -import-objc-header %S/Inputs/rdar29694978.h -emit-module -o %t/Library.swiftmodule
+// FIXME: Crashes with PCH (https://github.com/swiftlang/swift/issues/76641)
+// RUN: %target-build-swift %s -disable-bridging-pch -import-objc-header %S/Inputs/rdar29694978.h -emit-module -o %t/Library.swiftmodule
 // RUN: %target-swift-ide-test -print-module -module-to-print=Library -source-filename=x -I %S/Inputs/ -I %t | %FileCheck %s
 
 // REQUIRES: objc_interop
diff --git a/validation-test/execution/interpret-with-dependencies.swift b/validation-test/execution/interpret-with-dependencies.swift
index 166d98e253fd6..c8edff6cc8aeb 100644
--- a/validation-test/execution/interpret-with-dependencies.swift
+++ b/validation-test/execution/interpret-with-dependencies.swift
@@ -8,17 +8,6 @@
 // RUN: %swift_driver -I %S/Inputs/custom-modules -L%t %s | %FileCheck %s
 // CHECK: {{okay}}
 
-// Now test a dependency on a library in the compiler's resource directory.
-// RUN: %empty-directory(%t/rsrc/%target-sdk-name)
-// RUN: ln -s %t/libabc.dylib %t/rsrc/%target-sdk-name/
-// RUN: ln -s %platform-module-dir/* %t/rsrc/%target-sdk-name/
-// RUN: ln -s %platform-module-dir/../shims %t/rsrc/
-// RUN: %empty-directory(%t/other)
-// RUN: ln -s %t/libfoo.dylib %t/other
-
-// Disabled, because it fails on some CI jobs with "missing required module 'SwiftShims'"
-// dontrun: %swift_driver -I %S/Inputs/custom-modules -L%t/other -resource-dir %t/rsrc/ %s | %FileCheck %s
-
 import foo
 
 if test() == 42 {