build: fix accidental cmake expansions

As of CMake 3.25, there are now global variables `LINUX=1`, `ANDROID=1`, etc. These conflict with expressions that used these names as unquoted strings in positions where CMake accepts 'variable|string', for example: - `if(sdk STREQUAL LINUX)` would fail, because `LINUX` is now defined and expands to 1, where it would previously coerce to a string. - `if(${sdk} STREQUAL "LINUX")` would fail if `sdk=LINUX`, because the left-hand side expands twice. In this patch, I looked for a number of patterns to fix up, sometimes a little defensively: - Quoted right-hand side of `STREQUAL` where I was confident it was intended to be a string literal. - Removed manual variable expansion on left-hand side of `STREQUAL`, `MATCHES` and `IN_LIST` where I was confident it was unintended. Fixes apple#65028.
stephank · Apr 30, 2023 · 112681f · 112681f
1 parent f9611bc
commit 112681f
Show file tree

Hide file tree

Showing 37 changed files with 186 additions and 186 deletions.
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -119,7 +119,7 @@ else()
   if(CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64|AMD64|amd64")
     set(SWIFT_HOST_VARIANT_ARCH_default "x86_64")
   elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|ARM64|arm64")
-    if(SWIFT_HOST_VARIANT_SDK_default STREQUAL OSX)
+    if(SWIFT_HOST_VARIANT_SDK_default STREQUAL "OSX")
       set(SWIFT_HOST_VARIANT_ARCH_default "arm64")
     else()
       set(SWIFT_HOST_VARIANT_ARCH_default "aarch64")
@@ -336,7 +336,7 @@ set(SWIFT_STDLIB_BUILD_TYPE "${CMAKE_BUILD_TYPE}" CACHE STRING
 #   - MultiThreadedDebug (/MTd)
 #   - MultiThreadedDLL (/MD)
 #   - MultiThreadedDebugDLL (/MDd)
-if(CMAKE_BUILD_TYPE STREQUAL Debug)
+if(CMAKE_BUILD_TYPE STREQUAL "Debug")
   set(SWIFT_STDLIB_MSVC_RUNTIME_LIBRARY_default MultiThreadedDebugDLL)
 else()
   set(SWIFT_STDLIB_MSVC_RUNTIME_LIBRARY_default MultiThreadedDLL)
@@ -598,7 +598,7 @@ if(SWIFT_BUILT_STANDALONE)
   project(Swift C CXX ASM)
 endif()
 
-if(MSVC OR "${CMAKE_SIMULATE_ID}" STREQUAL MSVC)
+if(MSVC OR "${CMAKE_SIMULATE_ID}" STREQUAL "MSVC")
   include(ClangClCompileRules)
 elseif(UNIX)
   include(UnixCompileRules)
@@ -627,7 +627,7 @@ if(SWIFT_ENABLE_EXPERIMENTAL_CONCURRENCY AND "${SWIFT_CONCURRENCY_GLOBAL_EXECUTO
 endif()
 
 set(SWIFT_BUILD_HOST_DISPATCH FALSE)
-if(SWIFT_ENABLE_DISPATCH AND NOT CMAKE_SYSTEM_NAME STREQUAL Darwin)
+if(SWIFT_ENABLE_DISPATCH AND NOT CMAKE_SYSTEM_NAME STREQUAL "Darwin")
   # Only build libdispatch for the host if the host tools are being built and
   # specifically if these two libraries that depend on it are built.
   if(SWIFT_INCLUDE_TOOLS AND SWIFT_BUILD_SOURCEKIT)
@@ -801,11 +801,11 @@ endif()
 # build environment.
 if(LLVM_USE_LINKER)
   set(SWIFT_USE_LINKER_default "${LLVM_USE_LINKER}")
-elseif(${SWIFT_HOST_VARIANT_SDK} STREQUAL ANDROID)
+elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID")
   set(SWIFT_USE_LINKER_default "lld")
-elseif(CMAKE_SYSTEM_NAME STREQUAL Windows AND NOT CMAKE_HOST_SYSTEM_NAME STREQUAL Windows)
+elseif(CMAKE_SYSTEM_NAME STREQUAL "Windows" AND NOT CMAKE_HOST_SYSTEM_NAME STREQUAL "Windows")
   set(SWIFT_USE_LINKER_default "lld")
-elseif(CMAKE_SYSTEM_NAME STREQUAL Darwin)
+elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
   set(SWIFT_USE_LINKER_default "")
 else()
   set(SWIFT_USE_LINKER_default "gold")

diff --git a/SwiftCompilerSources/CMakeLists.txt b/SwiftCompilerSources/CMakeLists.txt
@@ -80,7 +80,7 @@ function(add_swift_compiler_modules_library name)
     list(APPEND swift_compile_options "-Xfrontend" "-disable-implicit-string-processing-module-import")
   endif()
 
-  if(CMAKE_BUILD_TYPE STREQUAL Debug)
+  if(CMAKE_BUILD_TYPE STREQUAL "Debug")
     list(APPEND swift_compile_options "-g")
   else()
     list(APPEND swift_compile_options "-O" "-cross-module-optimization")
@@ -98,7 +98,7 @@ function(add_swift_compiler_modules_library name)
     set(deployment_version "${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_DEPLOYMENT_VERSION}")
     set(sdk_path "${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_ARCH_${SWIFT_HOST_VARIANT_ARCH}_PATH}")
     set(sdk_option "-sdk" "${sdk_path}")
-    if(${BOOTSTRAPPING_MODE} STREQUAL "CROSSCOMPILE-WITH-HOSTLIBS")
+    if(BOOTSTRAPPING_MODE STREQUAL "CROSSCOMPILE-WITH-HOSTLIBS")
       # Let the cross-compiled compile don't pick up the compiled stdlib by providing
       # an (almost) empty resource dir.
       # The compiler will instead pick up the stdlib from the SDK.
@@ -117,7 +117,7 @@ function(add_swift_compiler_modules_library name)
         message(ERROR "libc++ not found in the toolchain.")
       endif()
     endif()
-  elseif(${BOOTSTRAPPING_MODE} STREQUAL "CROSSCOMPILE")
+  elseif(BOOTSTRAPPING_MODE STREQUAL "CROSSCOMPILE")
     set(sdk_option "-sdk" "${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_ARCH_${SWIFT_HOST_VARIANT_ARCH}_PATH}")
     get_filename_component(swift_exec_bin_dir ${ALS_SWIFT_EXEC} DIRECTORY)
     set(sdk_option ${sdk_option} "-resource-dir" "${swift_exec_bin_dir}/../lib/swift")
@@ -253,13 +253,13 @@ else()
   add_dependencies(importedHeaderDependencies swift-ast-generated-headers)
   target_include_directories(importedHeaderDependencies PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../include/swift")
 
-  if(${BOOTSTRAPPING_MODE} MATCHES "HOSTTOOLS|CROSSCOMPILE")
+  if(BOOTSTRAPPING_MODE MATCHES "HOSTTOOLS|CROSSCOMPILE")
 
     if (NOT SWIFT_EXEC_FOR_SWIFT_MODULES)
       message(FATAL_ERROR "Need a swift toolchain building swift compiler sources")
     endif()
 
-    if(${BOOTSTRAPPING_MODE} STREQUAL "HOSTTOOLS")
+    if(BOOTSTRAPPING_MODE STREQUAL "HOSTTOOLS")
       if(NOT SWIFT_EXEC_FOR_SWIFT_MODULES STREQUAL CMAKE_Swift_COMPILER)
         message(FATAL_ERROR "The Swift compiler (${CMAKE_Swift_COMPILER}) differs from the Swift compiler in SWIFT_NATIVE_SWIFT_TOOLS_PATH (${SWIFT_NATIVE_SWIFT_TOOLS_PATH}/swiftc).")
       endif()
@@ -275,11 +275,11 @@ else()
     add_swift_compiler_modules_library(swiftCompilerModules
       SWIFT_EXEC "${SWIFT_EXEC_FOR_SWIFT_MODULES}")
 
-  elseif(${BOOTSTRAPPING_MODE} MATCHES "BOOTSTRAPPING.*")
+  elseif(BOOTSTRAPPING_MODE MATCHES "BOOTSTRAPPING.*")
 
     set(b0_deps swift-frontend-bootstrapping0 symlink-headers-bootstrapping0)
     set(b1_deps swift-frontend-bootstrapping1 symlink-headers-bootstrapping1)
-    if(${BOOTSTRAPPING_MODE} STREQUAL "BOOTSTRAPPING")
+    if(BOOTSTRAPPING_MODE STREQUAL "BOOTSTRAPPING")
       list(APPEND b0_deps swiftCore-bootstrapping0)
       list(APPEND b1_deps swiftCore-bootstrapping1)
       if(CMAKE_BUILD_TYPE STREQUAL "Debug")
@@ -290,7 +290,7 @@ else()
         list(APPEND b0_deps swiftDarwin-bootstrapping0)
         list(APPEND b1_deps swiftDarwin-bootstrapping1)
       endif()
-      if(${SWIFT_HOST_VARIANT_SDK} IN_LIST SWIFT_LIBSTDCXX_PLATFORMS)
+      if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_LIBSTDCXX_PLATFORMS)
         list(APPEND b0_deps copy-libstdcxx-modulemap-bootstrapping0 copy-libstdcxx-header-bootstrapping0)
         list(APPEND b1_deps copy-libstdcxx-modulemap-bootstrapping1 copy-libstdcxx-header-bootstrapping1)
       endif()

diff --git a/benchmark/cmake/modules/AddSwiftBenchmarkSuite.cmake b/benchmark/cmake/modules/AddSwiftBenchmarkSuite.cmake
@@ -21,7 +21,7 @@ macro(configure_build)
     # thus allowing the --host-cc build-script argument to work here.
     get_filename_component(c_compiler ${CMAKE_C_COMPILER} NAME)
 
-    if(${c_compiler} STREQUAL "clang")
+    if(c_compiler STREQUAL "clang")
       set(CLANG_EXEC ${CMAKE_C_COMPILER})
     else()
       if(NOT SWIFT_DARWIN_XCRUN_TOOLCHAIN)
@@ -713,7 +713,7 @@ function(swift_benchmark_compile)
 
   if(NOT SWIFT_BENCHMARK_BUILT_STANDALONE)
     set(stdlib_dependencies "swift-frontend" "swiftCore-${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_LIB_SUBDIR}")
-    if(${SWIFT_HOST_VARIANT_SDK} IN_LIST SWIFT_DARWIN_PLATFORMS)
+    if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
       list(APPEND stdlib_dependencies "swiftDarwin-${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_LIB_SUBDIR}")
     endif()
     foreach(stdlib_dependency ${UNIVERSAL_LIBRARY_NAMES_${SWIFT_BENCHMARK_COMPILE_PLATFORM}})

diff --git a/cmake/modules/AddSwift.cmake b/cmake/modules/AddSwift.cmake
@@ -63,16 +63,16 @@ function(_set_target_prefix_and_suffix target kind sdk)
   precondition(kind MESSAGE "kind is required")
   precondition(sdk MESSAGE "sdk is required")
 
-  if(${sdk} STREQUAL ANDROID)
-    if(${kind} STREQUAL STATIC)
+  if(sdk STREQUAL "ANDROID")
+    if(kind STREQUAL "STATIC")
       set_target_properties(${target} PROPERTIES PREFIX "lib" SUFFIX ".a")
-    elseif(${kind} STREQUAL SHARED)
+    elseif(kind STREQUAL "SHARED")
       set_target_properties(${target} PROPERTIES PREFIX "lib" SUFFIX ".so")
     endif()
-  elseif(${sdk} STREQUAL WINDOWS)
-    if(${kind} STREQUAL STATIC)
+  elseif(sdk STREQUAL "WINDOWS")
+    if(kind STREQUAL "STATIC")
       set_target_properties(${target} PROPERTIES PREFIX "" SUFFIX ".lib")
-    elseif(${kind} STREQUAL SHARED)
+    elseif(kind STREQUAL "SHARED")
       set_target_properties(${target} PROPERTIES PREFIX "" SUFFIX ".dll")
     endif()
   endif()
@@ -115,7 +115,7 @@ function(_add_host_variant_c_compile_link_flags name)
     set(DEPLOYMENT_VERSION "${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_DEPLOYMENT_VERSION}")
   endif()
 
-  if(SWIFT_HOST_VARIANT_SDK STREQUAL ANDROID)
+  if(SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID")
     set(DEPLOYMENT_VERSION ${SWIFT_ANDROID_API_LEVEL})
   endif()
 
@@ -151,7 +151,7 @@ function(_add_host_variant_c_compile_link_flags name)
     target_compile_options(${name} PRIVATE $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:--sysroot=${_sysroot}>)
   endif()
 
-  if(SWIFT_HOST_VARIANT_SDK STREQUAL ANDROID)
+  if(SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID")
     # Make sure the Android NDK lld is used.
     swift_android_tools_path(${SWIFT_HOST_VARIANT_ARCH} tools_path)
     target_compile_options(${name} PRIVATE $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:-B${tools_path}>)
@@ -223,7 +223,7 @@ function(_add_host_variant_c_compile_flags target)
     endif()
   endif()
 
-  if(SWIFT_HOST_VARIANT_SDK STREQUAL WINDOWS)
+  if(SWIFT_HOST_VARIANT_SDK STREQUAL "WINDOWS")
     # MSVC/clang-cl don't support -fno-pic or -fms-compatibility-version.
     if(NOT SWIFT_COMPILER_IS_MSVC_LIKE)
       target_compile_options(${target} PRIVATE
@@ -276,14 +276,14 @@ function(_add_host_variant_c_compile_flags target)
     # NOTE(compnerd) workaround LLVM invoking `add_definitions(-D_DEBUG)` which
     # causes failures for the runtime library when cross-compiling due to
     # undefined symbols from the standard library.
-    if(NOT CMAKE_BUILD_TYPE STREQUAL Debug)
+    if(NOT CMAKE_BUILD_TYPE STREQUAL "Debug")
       target_compile_options(${target} PRIVATE
         $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:-U_DEBUG>)
     endif()
   endif()
 
-  if(SWIFT_HOST_VARIANT_SDK STREQUAL ANDROID)
-    if(SWIFT_HOST_VARIANT_ARCH STREQUAL x86_64)
+  if(SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID")
+    if(SWIFT_HOST_VARIANT_ARCH STREQUAL "x86_64")
       # NOTE(compnerd) Android NDK 21 or lower will generate library calls to
       # `__sync_val_compare_and_swap_16` rather than lowering to the CPU's
       # `cmpxchg16b` instruction as the `cx16` feature is disabled due to a bug
@@ -317,15 +317,15 @@ function(_add_host_variant_c_compile_flags target)
       $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:-fprofile-instr-generate -fcoverage-mapping>)
   endif()
 
-  if((SWIFT_HOST_VARIANT_ARCH STREQUAL armv7 OR
-      SWIFT_HOST_VARIANT_ARCH STREQUAL aarch64) AND
-     (SWIFT_HOST_VARIANT_SDK STREQUAL LINUX OR
-      SWIFT_HOST_VARIANT_SDK STREQUAL ANDROID))
+  if((SWIFT_HOST_VARIANT_ARCH STREQUAL "armv7" OR
+      SWIFT_HOST_VARIANT_ARCH STREQUAL "aarch64") AND
+     (SWIFT_HOST_VARIANT_SDK STREQUAL "LINUX" OR
+      SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID"))
     target_compile_options(${target} PRIVATE $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:-funwind-tables>)
   endif()
 
   if(SWIFT_HOST_VARIANT_SDK STREQUAL "LINUX")
-    if(SWIFT_HOST_VARIANT_ARCH STREQUAL x86_64)
+    if(SWIFT_HOST_VARIANT_ARCH STREQUAL "x86_64")
       # this is the minimum architecture that supports 16 byte CAS, which is
       # necessary to avoid a dependency to libatomic
       target_compile_options(${target} PRIVATE $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:-march=core2>)
@@ -336,7 +336,7 @@ function(_add_host_variant_c_compile_flags target)
   # llvm/llvm-project@66395c9, which can cause incompatibilities with the Swift
   # frontend if not built the same way.
   if("${SWIFT_HOST_VARIANT_ARCH}" MATCHES "armv6|armv7|i686" AND
-     NOT (SWIFT_HOST_VARIANT_SDK STREQUAL ANDROID AND SWIFT_ANDROID_API_LEVEL LESS 24))
+     NOT (SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID" AND SWIFT_ANDROID_API_LEVEL LESS 24))
     target_compile_definitions(${target} PRIVATE
       $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:_LARGEFILE_SOURCE _FILE_OFFSET_BITS=64>)
   endif()
@@ -345,19 +345,19 @@ endfunction()
 function(_add_host_variant_link_flags target)
   _add_host_variant_c_compile_link_flags(${target})
 
-  if(SWIFT_HOST_VARIANT_SDK STREQUAL LINUX)
+  if(SWIFT_HOST_VARIANT_SDK STREQUAL "LINUX")
     target_link_libraries(${target} PRIVATE
       pthread
       dl)
     if("${SWIFT_HOST_VARIANT_ARCH}" MATCHES "armv5|armv6|armv7|i686")
       target_link_libraries(${target} PRIVATE atomic)
     endif()
-  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL FREEBSD)
+  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "FREEBSD")
     target_link_libraries(${target} PRIVATE
       pthread)
-  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL CYGWIN)
+  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "CYGWIN")
     # No extra libraries required.
-  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL WINDOWS)
+  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "WINDOWS")
     # We don't need to add -nostdlib using MSVC or clang-cl, as MSVC and
     # clang-cl rely on auto-linking entirely.
     if(NOT SWIFT_COMPILER_IS_MSVC_LIKE)
@@ -375,12 +375,12 @@ function(_add_host_variant_link_flags target)
     # the Windows SDK on case sensitive file systems.
     target_link_directories(${target} PRIVATE
       ${CMAKE_BINARY_DIR}/winsdk_lib_${SWIFT_HOST_VARIANT_ARCH}_symlinks)
-  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL HAIKU)
+  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "HAIKU")
     target_link_libraries(${target} PRIVATE
       bsd)
     target_link_options(${target} PRIVATE
       "SHELL:-Xlinker -Bsymbolic")
-  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL ANDROID)
+  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID")
     target_link_libraries(${target} PRIVATE
       dl
       log
@@ -422,7 +422,7 @@ function(_add_host_variant_link_flags target)
   #
   # TODO: Evaluate/enable -f{function,data}-sections --gc-sections for bfd,
   # gold, and lld.
-  if(NOT CMAKE_BUILD_TYPE STREQUAL Debug AND CMAKE_SYSTEM_NAME MATCHES Darwin)
+  if(NOT CMAKE_BUILD_TYPE STREQUAL "Debug" AND CMAKE_SYSTEM_NAME MATCHES Darwin)
     if (NOT SWIFT_DISABLE_DEAD_STRIPPING)
       # See rdar://48283130: This gives 6MB+ size reductions for swift and
       # SourceKitService, and much larger size reductions for sil-opt etc.
@@ -446,7 +446,7 @@ function(_add_swift_runtime_link_flags target relpath_to_lib_dir bootstrapping)
   # RPATH where Swift runtime can be found.
   set(swift_runtime_rpath)
 
-  if(${SWIFT_HOST_VARIANT_SDK} IN_LIST SWIFT_DARWIN_PLATFORMS)
+  if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
 
     set(sdk_dir "${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_ARCH_${SWIFT_HOST_VARIANT_ARCH}_PATH}/usr/lib/swift")
 
@@ -529,7 +529,7 @@ function(_add_swift_runtime_link_flags target relpath_to_lib_dir bootstrapping)
 
   elseif(SWIFT_HOST_VARIANT_SDK MATCHES "LINUX|ANDROID|OPENBSD|FREEBSD")
     set(swiftrt "swiftImageRegistrationObject${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_OBJECT_FORMAT}-${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_LIB_SUBDIR}-${SWIFT_HOST_VARIANT_ARCH}")
-    if(${ASRLF_BOOTSTRAPPING_MODE} MATCHES "HOSTTOOLS|CROSSCOMPILE")
+    if(ASRLF_BOOTSTRAPPING_MODE MATCHES "HOSTTOOLS|CROSSCOMPILE")
       # At build time and run time, link against the swift libraries in the
       # installed host toolchain.
       get_filename_component(swift_bin_dir ${SWIFT_EXEC_FOR_SWIFT_MODULES} DIRECTORY)
@@ -575,7 +575,7 @@ function(_add_swift_runtime_link_flags target relpath_to_lib_dir bootstrapping)
     # able to fall back to the SDK directory for libswiftCore et al.
     if (BOOTSTRAPPING_MODE MATCHES "BOOTSTRAPPING.*")
       if (NOT "${bootstrapping}" STREQUAL "1")
-        if(${SWIFT_HOST_VARIANT_SDK} IN_LIST SWIFT_DARWIN_PLATFORMS)
+        if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
           target_link_directories(${target} PRIVATE "${sdk_dir}")
 
           # Include the abi stable system stdlib in our rpath.
@@ -706,10 +706,10 @@ function(add_swift_host_library name)
   if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
     set_target_properties(${name} PROPERTIES
       INSTALL_NAME_DIR "@rpath")
-  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL LINUX)
+  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "LINUX")
     set_target_properties(${name} PROPERTIES
       INSTALL_RPATH "$ORIGIN")
-  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL CYGWIN)
+  elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "CYGWIN")
     set_target_properties(${name} PROPERTIES
       INSTALL_RPATH "$ORIGIN:/usr/lib/swift/cygwin")
   elseif(SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID")
@@ -731,18 +731,18 @@ function(add_swift_host_library name)
   endif()
 
   # Set compilation and link flags.
-  if(SWIFT_HOST_VARIANT_SDK STREQUAL WINDOWS)
+  if(SWIFT_HOST_VARIANT_SDK STREQUAL "WINDOWS")
     swift_windows_include_for_arch(${SWIFT_HOST_VARIANT_ARCH}
       ${SWIFT_HOST_VARIANT_ARCH}_INCLUDE)
     target_include_directories(${name} SYSTEM PRIVATE
       ${${SWIFT_HOST_VARIANT_ARCH}_INCLUDE})
 
-    if(libkind STREQUAL SHARED)
+    if(libkind STREQUAL "SHARED")
       target_compile_definitions(${name} PRIVATE
         _WINDLL)
     endif()
 
-    if(NOT ${CMAKE_C_COMPILER_ID} STREQUAL MSVC)
+    if(NOT CMAKE_C_COMPILER_ID STREQUAL "MSVC")
       swift_windows_get_sdk_vfs_overlay(ASHL_VFS_OVERLAY)
       # Both clang and clang-cl on Windows set CMAKE_C_SIMULATE_ID to MSVC.
       # We are using CMAKE_C_COMPILER_FRONTEND_VARIANT to detect the correct
@@ -770,7 +770,7 @@ function(add_swift_host_library name)
 
   set_target_properties(${name} PROPERTIES LINKER_LANGUAGE CXX)
 
-  if(${SWIFT_HOST_VARIANT_SDK} IN_LIST SWIFT_DARWIN_PLATFORMS)
+  if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
     target_link_options(${name} PRIVATE
       "LINKER:-compatibility_version,1")
     if(SWIFT_COMPILER_VERSION)
@@ -856,7 +856,7 @@ function(add_swift_host_tool executable)
     add_dependencies(${executable} ${LLVM_COMMON_DEPENDS})
   endif()
 
-  if(NOT ${ASHT_BOOTSTRAPPING} STREQUAL "")
+  if(NOT "${ASHT_BOOTSTRAPPING}" STREQUAL "")
     # Strip the "-bootstrapping<n>" suffix from the target name to get the base
     # executable name.
     string(REGEX REPLACE "-bootstrapping.*" "" executable_filename ${executable})
@@ -891,7 +891,7 @@ function(add_swift_host_tool executable)
     BINARY_DIR ${out_bin_dir}
     LIBRARY_DIR ${out_lib_dir})
 
-  if(SWIFT_HOST_VARIANT_SDK STREQUAL WINDOWS)
+  if(SWIFT_HOST_VARIANT_SDK STREQUAL "WINDOWS")
     swift_windows_include_for_arch(${SWIFT_HOST_VARIANT_ARCH}
       ${SWIFT_HOST_VARIANT_ARCH}_INCLUDE)
     target_include_directories(${executable} SYSTEM PRIVATE
@@ -913,8 +913,8 @@ function(add_swift_host_tool executable)
 
   if(SWIFT_SWIFT_PARSER)
     set(extra_relative_rpath "")
-    if(NOT ${ASHT_BOOTSTRAPPING} STREQUAL "")
-      if (${executable} MATCHES "-bootstrapping")
+    if(NOT "${ASHT_BOOTSTRAPPING}" STREQUAL "")
+      if(executable MATCHES "-bootstrapping")
         set(extra_relative_rpath "../")
       endif()
     endif()
@@ -938,7 +938,7 @@ function(add_swift_host_tool executable)
     target_link_options(${executable} PRIVATE "${lto_codegen_only_link_options}")
   endif()
 
-  if(NOT ${ASHT_SWIFT_COMPONENT} STREQUAL "no_component")
+  if(NOT ASHT_SWIFT_COMPONENT STREQUAL "no_component")
     add_dependencies(${ASHT_SWIFT_COMPONENT} ${executable})
     swift_install_in_component(TARGETS ${executable}
                                RUNTIME