[Fuchsia] Add LLDB options to stage 1 cmake.

[mysterymath]

Summary

LLVM_ENABLE_PROJECTS is automatically forwarded from stage 1 builds to
stage 2 builds, so setting FUCHSIA_ENABLE_LLDB has no effect on
two-stage builds.

Instead, add FUCHSIA_ENABLE_LLDB to the stage one build as well.

This also disables curses and libedit by default for now in both stage1
and stage 2 builds; these should be opt-in.

[haowei]

clang/cmake/caches/Fuchsia.cmake

167

You probably need a string(REPLACE ";" "|" value "${_FUCHSIA_ENABLE_PROJECTS}") after append a value. As by default cmake use | to separate items.
But do you actually need a _FUCHSIA_ENABLE_PROJECTS variable, couldn't you just append lldb at the end of LLVM_ENABLE_PROJECTS here?

[mysterymath]

clang/cmake/caches/Fuchsia.cmake

167

You probably need a string(REPLACE ";" "|" value "${_FUCHSIA_ENABLE_PROJECTS}") after append a value. As by default cmake use | to separate items.

Hm? CMake's list separator is the semicolon: https://cmake.org/cmake/help/latest/command/list.html

But do you actually need a _FUCHSIA_ENABLE_PROJECTS variable, couldn't you just append lldb at the end of LLVM_ENABLE_PROJECTS here?

(list APPEND ...) doesn't work on cache variables. If I were to use the (set CACHE FORCE) idiom instead, it would append lldb each time a configure occurs. The idea here is to have FUCHSIA_ENABLE_LLDB affect the defaults, but to respect whatever's already in the CMake cache otherwise.

[haowei]

LGTM, but please wait @phosek to approve it.

clang/cmake/caches/Fuchsia.cmake

167

Hm? CMake's list separator is the semicolon: https://cmake.org/cmake/help/latest/command/list.html

I see, I am wrong. I thought it is similar to passthrough cmake variables to the next stage.

(list APPEND ...) doesn't work on cache variables. If I were to use the (set CACHE FORCE) idiom instead, it would append lldb each time a configure occurs. The idea here is to have FUCHSIA_ENABLE_LLDB affect the defaults, but to respect whatever's already in the CMake cache otherwise.

I see. I didn't know that.

[phosek]

LLVM_ENABLE_PROJECTS is automatically forwarded from stage 1 builds to
stage 2 builds, so setting FUCHSIA_ENABLE_LLDB has no effect on
two-stage builds.

That shouldn't be the case, do you know where it's being passed through?

[phosek]

In D145449#4175864, @phosek wrote:

LLVM_ENABLE_PROJECTS is automatically forwarded from stage 1 builds to
stage 2 builds, so setting FUCHSIA_ENABLE_LLDB has no effect on
two-stage builds.

That shouldn't be the case, do you know where it's being passed through?

Looks like it's being passed through here https://github.com/llvm/llvm-project/blob/c0e9c55db3b6a2a1287ba96ef3d378b97b72714a/clang/CMakeLists.txt#L669 which was introduced by D40258. I'll see if we can remove that.

clang/cmake/caches/Fuchsia-stage2.cmake

 set(LLVM_ENABLE_TERMINFO OFF CACHE BOOL "")
 set(LLVM_ENABLE_UNWIND_TABLES OFF CACHE BOOL "")
 set(LLVM_ENABLE_Z3_SOLVER OFF CACHE BOOL "")
 set(LLVM_ENABLE_ZLIB ON CACHE BOOL "")
 set(LLVM_INCLUDE_DOCS OFF CACHE BOOL "")
 set(LLVM_INCLUDE_EXAMPLES OFF CACHE BOOL "")
 set(LLVM_STATIC_LINK_CXX_STDLIB ON CACHE BOOL "")
 set(LLVM_USE_RELATIVE_PATHS_IN_FILES ON CACHE BOOL "")
+set(LLDB_ENABLE_CURSES OFF CACHE BOOL "")
+set(LLDB_ENABLE_LIBEDIT OFF CACHE BOOL "")
 
 if(WIN32)
   set(LLVM_USE_CRT_RELEASE "MT" CACHE STRING "")
 else()
   set(LLVM_TOOL_LLVM_DRIVER_BUILD ON CACHE BOOL "")
   set(LLVM_DRIVER_TARGET llvm-driver)
 endif()
 

clang/cmake/caches/Fuchsia.cmake

 # This file sets up a CMakeCache for a Fuchsia toolchain build.
 
 set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64;RISCV CACHE STRING "")
 
 set(PACKAGE_VENDOR Fuchsia CACHE STRING "")
 
-set(LLVM_ENABLE_PROJECTS "bolt;clang;clang-tools-extra;lld;llvm;polly" CACHE STRING "")
+set(_FUCHSIA_ENABLE_PROJECTS "bolt;clang;clang-tools-extra;lld;llvm;polly")
 
 set(LLVM_ENABLE_DIA_SDK OFF CACHE BOOL "")
 set(LLVM_ENABLE_LIBEDIT OFF CACHE BOOL "")
 set(LLVM_ENABLE_LIBXML2 OFF CACHE BOOL "")
 set(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR ON CACHE BOOL "")
 set(LLVM_ENABLE_TERMINFO OFF CACHE BOOL "")
 set(LLVM_ENABLE_UNWIND_TABLES OFF CACHE BOOL "")
 set(LLVM_ENABLE_Z3_SOLVER OFF CACHE BOOL "")
 set(LLVM_ENABLE_ZLIB OFF CACHE BOOL "")
 set(LLVM_INCLUDE_DOCS OFF CACHE BOOL "")
 set(LLVM_INCLUDE_EXAMPLES OFF CACHE BOOL "")
 set(LLVM_USE_RELATIVE_PATHS_IN_FILES ON CACHE BOOL "")
+set(LLDB_ENABLE_CURSES OFF CACHE BOOL "")
+set(LLDB_ENABLE_LIBEDIT OFF CACHE BOOL "")
 
 # Passthrough stage1 flags to stage1.
 set(_FUCHSIA_BOOTSTRAP_PASSTHROUGH
   LLVM_ENABLE_ZLIB
   ZLIB_INCLUDE_DIR
   ZLIB_LIBRARY
   LLVM_ENABLE_ZSTD
   zstd_DIR
   LLVM_ENABLE_LIBXML2
   LibXml2_ROOT
   LLVM_ENABLE_CURL
   CURL_ROOT
   OpenSSL_ROOT
+  FUCHSIA_ENABLE_LLDB
+  LLDB_ENABLE_CURSES
+  LLDB_ENABLE_LIBEDIT
   CMAKE_FIND_PACKAGE_PREFER_CONFIG
   CMAKE_SYSROOT
   CMAKE_MODULE_LINKER_FLAGS
   CMAKE_SHARED_LINKER_FLAGS
   CMAKE_EXE_LINKER_FLAGS
   LLVM_WINSYSROOT
   LLVM_VFSOVERLAY
 )
set(CLANG_BOOTSTRAP_TARGETS
   test-suite
   test-depends
   distribution
   install-distribution
   install-distribution-stripped
   install-distribution-toolchain
   clang CACHE STRING "")
 
+set(FUCHSIA_ENABLE_LLDB OFF CACHE BOOL "Enable LLDB")
+if(FUCHSIA_ENABLE_LLDB)
+  list(APPEND _FUCHSIA_ENABLE_PROJECTS lldb)
+endif()
+set(LLVM_ENABLE_PROJECTS ${_FUCHSIA_ENABLE_PROJECTS} CACHE STRING "")
+
 get_cmake_property(variableNames VARIABLES)
 foreach(variableName ${variableNames})
   if(variableName MATCHES "^STAGE2_")
     string(REPLACE "STAGE2_" "" new_name ${variableName})
     list(APPEND EXTRA_ARGS "-D${new_name}=${${variableName}}")
   endif()
 endforeach()