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 #65028.

Author: stephank

CMakeLists.txt

@@ -50,7 +50,7 @@ enable_language(CXX)
 set(SWIFT_ASM_DIALECT ASM)
 set(SWIFT_ASM_EXT S)
 set(SWIFT_ASM_AVAILABLE YES)
-if(CMAKE_SYSTEM_NAME STREQUAL Windows)
+if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
   if(CMAKE_SYSTEM_PROCESSOR MATCHES "ARM64")
     if(CMAKE_VERSION VERSION_LESS "3.26")
       message(warning "We can't build assembly language for ARM64 until CMake 3.26")
@@ -158,7 +158,7 @@ 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")
@@ -380,7 +380,7 @@ 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)
@@ -675,7 +675,7 @@ if(SWIFT_BUILT_STANDALONE)
   project(Swift C CXX ${SWIFT_ASM_DIALECT})
 endif()
 
-if(MSVC OR "${CMAKE_SIMULATE_ID}" STREQUAL MSVC)
+if(MSVC OR "${CMAKE_SIMULATE_ID}" STREQUAL "MSVC")
   include(ClangClCompileRules)
 elseif(UNIX)
   include(UnixCompileRules)
@@ -697,7 +697,7 @@ if(NOT EXISTS "${SWIFT_PATH_TO_SWIFT_SYNTAX_SOURCE}")
 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)
@@ -883,11 +883,11 @@ 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")

SwiftCompilerSources/CMakeLists.txt

@@ -81,7 +81,7 @@ 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")
@@ -103,7 +103,7 @@ 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(${BOOTSTRAPPING_MODE} STREQUAL "CROSSCOMPILE-WITH-HOSTLIBS")
+    if(BOOTSTRAPPING_MODE STREQUAL "CROSSCOMPILE-WITH-HOSTLIBS")
       # Let the cross-compiled compile don't pick up the compiled stdlib by providing
       # an (almost) empty resource dir.
       # The compiler will instead pick up the stdlib from the SDK.
@@ -122,7 +122,7 @@ function(add_swift_compiler_modules_library name)
         message(ERROR "libc++ not found in the toolchain.")
       endif()
     endif()
-  elseif(${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")
@@ -259,13 +259,13 @@ 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 (${SWIFT_NATIVE_SWIFT_TOOLS_PATH}/swiftc).")
       endif()
@@ -281,11 +281,11 @@ else()
     add_swift_compiler_modules_library(swiftCompilerModules
       SWIFT_EXEC "${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(${BOOTSTRAPPING_MODE} STREQUAL "BOOTSTRAPPING")
+    if(BOOTSTRAPPING_MODE STREQUAL "BOOTSTRAPPING")
       list(APPEND b0_deps swiftCore-bootstrapping0)
       list(APPEND b1_deps swiftCore-bootstrapping1)
       if(CMAKE_BUILD_TYPE STREQUAL "Debug")
@@ -296,7 +296,7 @@ else()
         list(APPEND b0_deps swiftDarwin-bootstrapping0)
         list(APPEND b1_deps swiftDarwin-bootstrapping1)
       endif()
-      if(${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()

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}})

cmake/modules/AddPureSwift.cmake

@@ -53,7 +53,7 @@ function(_add_host_swift_compile_options 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()
 
@@ -141,7 +141,7 @@ function(add_pure_swift_host_library name)
   set_property(TARGET ${name}
     PROPERTY BUILD_WITH_INSTALL_RPATH YES)
 
-  if(APSHL_SHARED AND CMAKE_SYSTEM_NAME STREQUAL Darwin)
+  if(APSHL_SHARED AND CMAKE_SYSTEM_NAME STREQUAL "Darwin")
     # Allow install_name_tool to update paths (for rdar://109473564)
     set_property(TARGET ${name} APPEND_STRING PROPERTY
                  LINK_FLAGS " -Xlinker -headerpad_max_install_names")
@@ -267,7 +267,7 @@ function(add_pure_swift_host_tool name)
   add_executable(${name} ${APSHT_SOURCES})
   _add_host_swift_compile_options(${name})
 
-  if(${SWIFT_HOST_VARIANT_SDK} IN_LIST SWIFT_DARWIN_PLATFORMS)
+  if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
     set_property(TARGET ${name}
       APPEND PROPERTY INSTALL_RPATH
         "@executable_path/../lib/swift/host")