[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

cyndyishida wrote:

> FYI, it looks like this change broke `compiler-rt` build, e.g. in 
> https://lab.llvm.org/buildbot/#/builders/270/builds/12485

Should be resolved by: 
https://github.com/llvm/llvm-project/commit/fe45029dbdee6b3df2dbeaed17c9dd598ec511f2
 
I suspect compiler-rt may be relying on defaults set by Apple* cmake caches on 
unrelated environments.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

@@ -1029,6 +1038,16 @@ macro(add_llvm_executable name)
 add_llvm_symbol_exports( ${name} ${LLVM_EXPORTED_SYMBOL_FILE} )
   endif(LLVM_EXPORTED_SYMBOL_FILE)
 
+  if (NOT LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES) 
+if(LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+  set_property(TARGET ${name} APPEND_STRING PROPERTY
+LINK_FLAGS " -Wl,-no_exported_symbols")
+else()
+  message(FATAL_ERROR 
+"LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES cannot be disabled when 
linker does not support \"-no_exported_symbols\"")

cyndyishida wrote:

Yea, theres more platform-friendly and older ways to achieve the same thing. I 
opted not to because AFAIK, our toolchain only builds with linkers that support 
the straightforward flag, and wasn't sure how useful this would be for other 
platforms. 

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Slava Zakharin via lldb-commits]

vzakhari wrote:

FYI, it looks like this change broke `compiler-rt` build, e.g. in 
https://lab.llvm.org/buildbot/#/builders/270/builds/12485

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dave Lee via lldb-commits]

@@ -1029,6 +1038,16 @@ macro(add_llvm_executable name)
 add_llvm_symbol_exports( ${name} ${LLVM_EXPORTED_SYMBOL_FILE} )
   endif(LLVM_EXPORTED_SYMBOL_FILE)
 
+  if (NOT LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES) 
+if(LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+  set_property(TARGET ${name} APPEND_STRING PROPERTY
+LINK_FLAGS " -Wl,-no_exported_symbols")
+else()
+  message(FATAL_ERROR 
+"LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES cannot be disabled when 
linker does not support \"-no_exported_symbols\"")

kastiglione wrote:

Prior to the addition of `-no_exported_symbols`, I used to use 
`-Wl,-exported_symbols_list,/dev/null` to achieve the same thing. That could be 
a fallback, if anyone is motivated.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

https://github.com/cyndyishida closed 
https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

https://github.com/delcypher edited 
https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

https://github.com/delcypher edited 
https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

https://github.com/delcypher edited 
https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -258,15 +258,24 @@ if (NOT DEFINED LLVM_LINKER_DETECTED AND NOT WIN32)
 endif()
   endif()
 
-  # Apple's linker complains about duplicate libraries, which CMake likes to do
-  # to support ELF platforms. To silence that warning, we can use
-  # -no_warn_duplicate_libraries, but only in versions of the linker that
-  # support that flag.
-  if(NOT LLVM_USE_LINKER AND ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 include(CheckLinkerFlag)
-check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
-  else()
-set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL "")
+# Linkers that support Darwin allow a setting to internalize all symbol 
exports, 
+# aiding in reducing binary size and often is applicable for executables.
+check_linker_flag(C "-Wl,-no_exported_symbols" 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+
+if (NOT LLVM_USE_LINKER) 
+  # Apple's linker complains about duplicate libraries, which CMake likes 
to do
+  # to support ELF platforms. To silence that warning, we can use
+  # -no_warn_duplicate_libraries, but only in versions of the linker that
+  # support that flag.
+  check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
+else()
+  set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL 
"")
+endif()
+  
+  else() 
+set(LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS OFF CACHE INTERNAL "")

delcypher wrote:

Ignore this suggestion. `INTERNAL` implies `FORCE`.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -258,15 +258,24 @@ if (NOT DEFINED LLVM_LINKER_DETECTED AND NOT WIN32)
 endif()
   endif()
 
-  # Apple's linker complains about duplicate libraries, which CMake likes to do
-  # to support ELF platforms. To silence that warning, we can use
-  # -no_warn_duplicate_libraries, but only in versions of the linker that
-  # support that flag.
-  if(NOT LLVM_USE_LINKER AND ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 include(CheckLinkerFlag)
-check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
-  else()
-set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL "")
+# Linkers that support Darwin allow a setting to internalize all symbol 
exports, 
+# aiding in reducing binary size and often is applicable for executables.
+check_linker_flag(C "-Wl,-no_exported_symbols" 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+
+if (NOT LLVM_USE_LINKER) 
+  # Apple's linker complains about duplicate libraries, which CMake likes 
to do
+  # to support ELF platforms. To silence that warning, we can use
+  # -no_warn_duplicate_libraries, but only in versions of the linker that
+  # support that flag.
+  check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
+else()
+  set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL 
"")

delcypher wrote:

Oh wait. Ignore me. Using `INTERNAL` implies `FORCE`.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

https://github.com/delcypher approved this pull request.

LGTM. Other than the nit about not using `FORCE` to set the CMake cache 
variable.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -258,15 +258,24 @@ if (NOT DEFINED LLVM_LINKER_DETECTED AND NOT WIN32)
 endif()
   endif()
 
-  # Apple's linker complains about duplicate libraries, which CMake likes to do
-  # to support ELF platforms. To silence that warning, we can use
-  # -no_warn_duplicate_libraries, but only in versions of the linker that
-  # support that flag.
-  if(NOT LLVM_USE_LINKER AND ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 include(CheckLinkerFlag)
-check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
-  else()
-set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL "")
+# Linkers that support Darwin allow a setting to internalize all symbol 
exports, 
+# aiding in reducing binary size and often is applicable for executables.
+check_linker_flag(C "-Wl,-no_exported_symbols" 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+
+if (NOT LLVM_USE_LINKER) 
+  # Apple's linker complains about duplicate libraries, which CMake likes 
to do
+  # to support ELF platforms. To silence that warning, we can use
+  # -no_warn_duplicate_libraries, but only in versions of the linker that
+  # support that flag.
+  check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
+else()
+  set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL 
"")
+endif()
+  
+  else() 
+set(LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS OFF CACHE INTERNAL "")

delcypher wrote:

Same here. Consider using `FORCE`

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -258,15 +258,24 @@ if (NOT DEFINED LLVM_LINKER_DETECTED AND NOT WIN32)
 endif()
   endif()
 
-  # Apple's linker complains about duplicate libraries, which CMake likes to do
-  # to support ELF platforms. To silence that warning, we can use
-  # -no_warn_duplicate_libraries, but only in versions of the linker that
-  # support that flag.
-  if(NOT LLVM_USE_LINKER AND ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 include(CheckLinkerFlag)
-check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
-  else()
-set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL "")
+# Linkers that support Darwin allow a setting to internalize all symbol 
exports, 
+# aiding in reducing binary size and often is applicable for executables.
+check_linker_flag(C "-Wl,-no_exported_symbols" 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+
+if (NOT LLVM_USE_LINKER) 
+  # Apple's linker complains about duplicate libraries, which CMake likes 
to do
+  # to support ELF platforms. To silence that warning, we can use
+  # -no_warn_duplicate_libraries, but only in versions of the linker that
+  # support that flag.
+  check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
+else()
+  set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL 
"")

delcypher wrote:

Nit: This won't do anything if 
`LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES` is already set in the cache 
(e.g. from a previous configure). You can use `FORCE` to always set the value.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

https://github.com/cyndyishida updated 
https://github.com/llvm/llvm-project/pull/87684

>From 3ac6872328334384fa20998541fac841add767d9 Mon Sep 17 00:00:00 2001
From: Cyndy Ishida 
Date: Thu, 4 Apr 2024 12:08:28 -0700
Subject: [PATCH 1/4] [cmake] Build executables with -no_exported_symbols when
 building Apple toolchain

Building the Apple way turns off plugin support, meaning we don't need to be 
exporting unloadable symbols from all executables.
While deadstripping effects aren't expected to change, enabling this across all 
tools prevents the creation of export tries. This saves us ~3.5 MB's in just 
the universal build of `clang`.
---
 clang/cmake/caches/Apple-stage2.cmake   |  1 +
 lldb/cmake/caches/Apple-lldb-base.cmake |  1 +
 llvm/CMakeLists.txt |  3 +++
 llvm/cmake/modules/AddLLVM.cmake| 30 ++---
 llvm/docs/CMake.rst |  4 
 5 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/clang/cmake/caches/Apple-stage2.cmake 
b/clang/cmake/caches/Apple-stage2.cmake
index 72cdedd611bc96..faf61fd1fe9ecb 100644
--- a/clang/cmake/caches/Apple-stage2.cmake
+++ b/clang/cmake/caches/Apple-stage2.cmake
@@ -15,6 +15,7 @@ set(LLVM_ENABLE_ZLIB ON CACHE BOOL "")
 set(LLVM_ENABLE_BACKTRACES OFF CACHE BOOL "")
 set(LLVM_ENABLE_MODULES ON CACHE BOOL "")
 set(LLVM_EXTERNALIZE_DEBUGINFO ON CACHE BOOL "")
+set(LLVM_ENABLE_NO_EXPORTED_SYMBOLS ON CACHE BOOL "")
 set(CLANG_PLUGIN_SUPPORT OFF CACHE BOOL "")
 set(CLANG_SPAWN_CC1 ON CACHE BOOL "")
 set(BUG_REPORT_URL "http://developer.apple.com/bugreporter/; CACHE STRING "")
diff --git a/lldb/cmake/caches/Apple-lldb-base.cmake 
b/lldb/cmake/caches/Apple-lldb-base.cmake
index 4d4f02bfae95bd..021538896b2346 100644
--- a/lldb/cmake/caches/Apple-lldb-base.cmake
+++ b/lldb/cmake/caches/Apple-lldb-base.cmake
@@ -3,6 +3,7 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON CACHE BOOL "")
 
 set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64 CACHE STRING "")
 set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
+set(LLVM_ENABLE_NO_EXPORTED_SYMBOLS ON CACHE BOOL "")
 
 set(LIBCXX_ENABLE_SHARED OFF CACHE BOOL "")
 set(LIBCXX_ENABLE_STATIC OFF CACHE BOOL "")
diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
index 6f5647d70d8bc1..7e393acacb80d8 100644
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_NO_EXPORTED_SYMBOLS
+  "When building executables, disable any symbol exports (Darwin Only)" OFF)
+
 set(LLVM_CODESIGNING_IDENTITY "" CACHE STRING
   "Sign executables and dylibs with the given identity or skip if empty 
(Darwin Only)")
 
diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
index 745935f1405170..141a97c852e24f 100644
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -258,15 +258,24 @@ if (NOT DEFINED LLVM_LINKER_DETECTED AND NOT WIN32)
 endif()
   endif()
 
-  # Apple's linker complains about duplicate libraries, which CMake likes to do
-  # to support ELF platforms. To silence that warning, we can use
-  # -no_warn_duplicate_libraries, but only in versions of the linker that
-  # support that flag.
-  if(NOT LLVM_USE_LINKER AND ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 include(CheckLinkerFlag)
-check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
-  else()
-set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL "")
+# Linkers that support Darwin allow a setting to internalize all symbol 
exports, 
+# aiding in reducing binary size and often is applicable for executables.
+check_linker_flag(C "-Wl,-no_exported_symbols" 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+
+if (NOT LLVM_USE_LINKER) 
+  # Apple's linker complains about duplicate libraries, which CMake likes 
to do
+  # to support ELF platforms. To silence that warning, we can use
+  # -no_warn_duplicate_libraries, but only in versions of the linker that
+  # support that flag.
+  check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
+else()
+  set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL 
"")
+endif()
+  
+  else() 
+set(LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS OFF CACHE INTERNAL "")
   endif()
 endif()
 
@@ -1029,6 +1038,11 @@ macro(add_llvm_executable name)
 add_llvm_symbol_exports( ${name} ${LLVM_EXPORTED_SYMBOL_FILE} )
   endif(LLVM_EXPORTED_SYMBOL_FILE)
 
+  if (LLVM_ENABLE_NO_EXPORTED_SYMBOLS AND 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+set_property(TARGET ${name} APPEND_STRING PROPERTY
+  LINK_FLAGS " -Wl,-no_exported_symbols")
+  endif()
+
   if (LLVM_LINK_LLVM_DYLIB AND NOT ARG_DISABLE_LLVM_LINK_LLVM_DYLIB)
 set(USE_SHARED USE_SHARED)
   

[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -1029,6 +1038,11 @@ macro(add_llvm_executable name)
 add_llvm_symbol_exports( ${name} ${LLVM_EXPORTED_SYMBOL_FILE} )
   endif(LLVM_EXPORTED_SYMBOL_FILE)
 
+  if (NOT LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES AND 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)

delcypher wrote:

Currently we silently ignore `LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES` if 
the linker doesn't support the flag. It would probably better to produce a 
fatal error to avoid an invalid configuration being used.

```cmake
if (NOT LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES)
  if (LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
  set_property(TARGET ${name} APPEND_STRING PROPERTY
  LINK_FLAGS " -Wl,-no_exported_symbols")
  else()
message(FATAL_ERROR "LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES cannot be 
disabled when linker does not support  \" -Wl,-no_exported_symbols\""
  endif()
endif()
```

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

https://github.com/cyndyishida updated 
https://github.com/llvm/llvm-project/pull/87684

>From 3ac6872328334384fa20998541fac841add767d9 Mon Sep 17 00:00:00 2001
From: Cyndy Ishida 
Date: Thu, 4 Apr 2024 12:08:28 -0700
Subject: [PATCH 1/3] [cmake] Build executables with -no_exported_symbols when
 building Apple toolchain

Building the Apple way turns off plugin support, meaning we don't need to be 
exporting unloadable symbols from all executables.
While deadstripping effects aren't expected to change, enabling this across all 
tools prevents the creation of export tries. This saves us ~3.5 MB's in just 
the universal build of `clang`.
---
 clang/cmake/caches/Apple-stage2.cmake   |  1 +
 lldb/cmake/caches/Apple-lldb-base.cmake |  1 +
 llvm/CMakeLists.txt |  3 +++
 llvm/cmake/modules/AddLLVM.cmake| 30 ++---
 llvm/docs/CMake.rst |  4 
 5 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/clang/cmake/caches/Apple-stage2.cmake 
b/clang/cmake/caches/Apple-stage2.cmake
index 72cdedd611bc96..faf61fd1fe9ecb 100644
--- a/clang/cmake/caches/Apple-stage2.cmake
+++ b/clang/cmake/caches/Apple-stage2.cmake
@@ -15,6 +15,7 @@ set(LLVM_ENABLE_ZLIB ON CACHE BOOL "")
 set(LLVM_ENABLE_BACKTRACES OFF CACHE BOOL "")
 set(LLVM_ENABLE_MODULES ON CACHE BOOL "")
 set(LLVM_EXTERNALIZE_DEBUGINFO ON CACHE BOOL "")
+set(LLVM_ENABLE_NO_EXPORTED_SYMBOLS ON CACHE BOOL "")
 set(CLANG_PLUGIN_SUPPORT OFF CACHE BOOL "")
 set(CLANG_SPAWN_CC1 ON CACHE BOOL "")
 set(BUG_REPORT_URL "http://developer.apple.com/bugreporter/; CACHE STRING "")
diff --git a/lldb/cmake/caches/Apple-lldb-base.cmake 
b/lldb/cmake/caches/Apple-lldb-base.cmake
index 4d4f02bfae95bd..021538896b2346 100644
--- a/lldb/cmake/caches/Apple-lldb-base.cmake
+++ b/lldb/cmake/caches/Apple-lldb-base.cmake
@@ -3,6 +3,7 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON CACHE BOOL "")
 
 set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64 CACHE STRING "")
 set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
+set(LLVM_ENABLE_NO_EXPORTED_SYMBOLS ON CACHE BOOL "")
 
 set(LIBCXX_ENABLE_SHARED OFF CACHE BOOL "")
 set(LIBCXX_ENABLE_STATIC OFF CACHE BOOL "")
diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
index 6f5647d70d8bc1..7e393acacb80d8 100644
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_NO_EXPORTED_SYMBOLS
+  "When building executables, disable any symbol exports (Darwin Only)" OFF)
+
 set(LLVM_CODESIGNING_IDENTITY "" CACHE STRING
   "Sign executables and dylibs with the given identity or skip if empty 
(Darwin Only)")
 
diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
index 745935f1405170..141a97c852e24f 100644
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -258,15 +258,24 @@ if (NOT DEFINED LLVM_LINKER_DETECTED AND NOT WIN32)
 endif()
   endif()
 
-  # Apple's linker complains about duplicate libraries, which CMake likes to do
-  # to support ELF platforms. To silence that warning, we can use
-  # -no_warn_duplicate_libraries, but only in versions of the linker that
-  # support that flag.
-  if(NOT LLVM_USE_LINKER AND ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 include(CheckLinkerFlag)
-check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
-  else()
-set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL "")
+# Linkers that support Darwin allow a setting to internalize all symbol 
exports, 
+# aiding in reducing binary size and often is applicable for executables.
+check_linker_flag(C "-Wl,-no_exported_symbols" 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+
+if (NOT LLVM_USE_LINKER) 
+  # Apple's linker complains about duplicate libraries, which CMake likes 
to do
+  # to support ELF platforms. To silence that warning, we can use
+  # -no_warn_duplicate_libraries, but only in versions of the linker that
+  # support that flag.
+  check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
+else()
+  set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL 
"")
+endif()
+  
+  else() 
+set(LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS OFF CACHE INTERNAL "")
   endif()
 endif()
 
@@ -1029,6 +1038,11 @@ macro(add_llvm_executable name)
 add_llvm_symbol_exports( ${name} ${LLVM_EXPORTED_SYMBOL_FILE} )
   endif(LLVM_EXPORTED_SYMBOL_FILE)
 
+  if (LLVM_ENABLE_NO_EXPORTED_SYMBOLS AND 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+set_property(TARGET ${name} APPEND_STRING PROPERTY
+  LINK_FLAGS " -Wl,-no_exported_symbols")
+  endif()
+
   if (LLVM_LINK_LLVM_DYLIB AND NOT ARG_DISABLE_LLVM_LINK_LLVM_DYLIB)
 set(USE_SHARED USE_SHARED)
   

[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Jonas Devlieghere via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_EXPORTED_SYMBOLS

JDevlieghere wrote:

@delcypher I was referring to the tools in `/llvm-project/llvm/tools`, which 
use `add_llvm_tool_subdirectory` and `add_llvm_tool` but maybe the distinction 
is more murky than I think it is. I'm also fine with `EXECUTABLE` in the name 

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -654,6 +654,11 @@ enabled sub-projects. Nearly all of these variable names 
begin with
   Generate dSYM files and strip executables and libraries (Darwin Only).
   Defaults to OFF.
 
+**LLVM_ENABLE_EXPORTED_SYMBOLS**:BOOL
+  When building executables, preserve symbol exports. Defaults to ON. 
+  You can use this option to disable exported symbols on all executable build

delcypher wrote:

Well if there's precedent I guess you can go either way. I'm personally not a 
fan but you should go with whatever you prefer.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_EXPORTED_SYMBOLS

delcypher wrote:

@JDevlieghere 
> "tools" has a pretty specific meaning for LLVM so I think that will actually 
> cause more confusion (i.e. I would expect that option to apply to 
> llvm-dwarfdump, but not to clang). I'm personally fine with the current 
> concise name.

I'm not exactly sure what that "specific meaning" is but I'm happy to go with 
something else. I think using the name "EXECUTABLE" as @cyndyishida is 
suggesting is consistent with the option being used in the 
`add_llvm_executable()` macro.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

https://github.com/delcypher deleted 
https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_EXPORTED_SYMBOLS

delcypher wrote:

> "tools" has a pretty specific meaning for LLVM so I think that will actually 
> cause more confusion (i.e. I would expect that option to apply to 
> llvm-dwarfdump, but not to clang). I'm personally fine with the current 
> concise name.

I'm not exactly sure what that "specific meaning" is but I'm happy to go with 
something else. I think using the name "EXECUTABLE" as @cyndyishida is 
suggesting is consistent with the option being used in `add_llvm_executable()`.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_EXPORTED_SYMBOLS

danliew-apple wrote:

I'm fine with that. You could also do 
`LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES` which is ever so slightly shorter 
路‍♂️

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_EXPORTED_SYMBOLS

cyndyishida wrote:

Would `LLVM_ENABLE_EXECUTABLES_WITH_EXPORTED_SYMBOLS` be too long?

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Jonas Devlieghere via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_EXPORTED_SYMBOLS

JDevlieghere wrote:

"tools" has a pretty specific meaning for LLVM so I think that will actually 
cause more confusion (i.e. I would expect that option to apply to 
`llvm-dwarfdump`, but not to `clang`). I'm personally fine with the current 
concise name. 

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

@@ -654,6 +654,11 @@ enabled sub-projects. Nearly all of these variable names 
begin with
   Generate dSYM files and strip executables and libraries (Darwin Only).
   Defaults to OFF.
 
+**LLVM_ENABLE_EXPORTED_SYMBOLS**:BOOL
+  When building executables, preserve symbol exports. Defaults to ON. 
+  You can use this option to disable exported symbols on all executable build

cyndyishida wrote:

That's what I initially thought as well but a lot of the LLVM_INCLUDE* 
variables on the lines below follow a "You can use this option..." And they 
also have similar behavior which defaults to ON. 

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -654,6 +654,11 @@ enabled sub-projects. Nearly all of these variable names 
begin with
   Generate dSYM files and strip executables and libraries (Darwin Only).
   Defaults to OFF.
 
+**LLVM_ENABLE_EXPORTED_SYMBOLS**:BOOL
+  When building executables, preserve symbol exports. Defaults to ON. 
+  You can use this option to disable exported symbols on all executable build

delcypher wrote:

Nit: Documentation tends not to use "You" as the subject.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

https://github.com/delcypher requested changes to this pull request.

Generally looks good. I have some minor nits. I'd like to see 
`LLVM_ENABLE_EXPORTED_SYMBOLS` renamed to avoid ambiguity.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -654,6 +654,11 @@ enabled sub-projects. Nearly all of these variable names 
begin with
   Generate dSYM files and strip executables and libraries (Darwin Only).
   Defaults to OFF.
 
+**LLVM_ENABLE_EXPORTED_SYMBOLS**:BOOL
+  When building executables, preserve symbol exports. Defaults to ON. 
+  You can use this option to disable exported symbols on all executable build

delcypher wrote:

```suggestion
  Setting this option to ``OFF`` removes exported symbols from all executables.
```

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_EXPORTED_SYMBOLS

delcypher wrote:

We may want to rename this. The name hints that this option applies to 
everything but actually it only applies to executables and not libraries. E.g. 
`LLVM_ENABLE_TOOLS_WITH_EXPORTED_SYMBOLS`

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dan Liew via lldb-commits]

https://github.com/delcypher edited 
https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Jon Roelofs via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_NO_EXPORTED_SYMBOLS

jroelofs wrote:

Flags like this shouldn't have `DISABLE` in their name either. It's 
ambiguous/confusing whether `LLVM_DISABLE_THING=On` means THING=ON or THING=Off.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[via lldb-commits]

jimingham wrote:

lldb can and does present its external symbol interface through LLDB.framework. 
 I can't see any reason why it would also need to export symbols from the 
executable.  The lldb driver is just a fairly small convenience wrapper around 
the API's from LLDB.framework, its job is to handle command-line arguments and 
start up a debugger from LLDB.framework.

Jim 

> On Apr 4, 2024, at 2:01 PM, Dave Lee ***@***.***> wrote:
> 
> 
> Thanks for adding this! I've been using CMAKE_EXE_LINKER_FLAGS to 
> -Wl,-no_exported_symbols, and have had no problems.
> 
> —
> Reply to this email directly, view it on GitHub 
> , or 
> unsubscribe 
> .
> You are receiving this because you are on a team that was mentioned.
> 



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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_NO_EXPORTED_SYMBOLS

cyndyishida wrote:

No preference here. Whatever seems easier for others to understand.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Cyndy Ishida via lldb-commits]

https://github.com/cyndyishida updated 
https://github.com/llvm/llvm-project/pull/87684

>From 3ac6872328334384fa20998541fac841add767d9 Mon Sep 17 00:00:00 2001
From: Cyndy Ishida 
Date: Thu, 4 Apr 2024 12:08:28 -0700
Subject: [PATCH 1/2] [cmake] Build executables with -no_exported_symbols when
 building Apple toolchain

Building the Apple way turns off plugin support, meaning we don't need to be 
exporting unloadable symbols from all executables.
While deadstripping effects aren't expected to change, enabling this across all 
tools prevents the creation of export tries. This saves us ~3.5 MB's in just 
the universal build of `clang`.
---
 clang/cmake/caches/Apple-stage2.cmake   |  1 +
 lldb/cmake/caches/Apple-lldb-base.cmake |  1 +
 llvm/CMakeLists.txt |  3 +++
 llvm/cmake/modules/AddLLVM.cmake| 30 ++---
 llvm/docs/CMake.rst |  4 
 5 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/clang/cmake/caches/Apple-stage2.cmake 
b/clang/cmake/caches/Apple-stage2.cmake
index 72cdedd611bc96..faf61fd1fe9ecb 100644
--- a/clang/cmake/caches/Apple-stage2.cmake
+++ b/clang/cmake/caches/Apple-stage2.cmake
@@ -15,6 +15,7 @@ set(LLVM_ENABLE_ZLIB ON CACHE BOOL "")
 set(LLVM_ENABLE_BACKTRACES OFF CACHE BOOL "")
 set(LLVM_ENABLE_MODULES ON CACHE BOOL "")
 set(LLVM_EXTERNALIZE_DEBUGINFO ON CACHE BOOL "")
+set(LLVM_ENABLE_NO_EXPORTED_SYMBOLS ON CACHE BOOL "")
 set(CLANG_PLUGIN_SUPPORT OFF CACHE BOOL "")
 set(CLANG_SPAWN_CC1 ON CACHE BOOL "")
 set(BUG_REPORT_URL "http://developer.apple.com/bugreporter/; CACHE STRING "")
diff --git a/lldb/cmake/caches/Apple-lldb-base.cmake 
b/lldb/cmake/caches/Apple-lldb-base.cmake
index 4d4f02bfae95bd..021538896b2346 100644
--- a/lldb/cmake/caches/Apple-lldb-base.cmake
+++ b/lldb/cmake/caches/Apple-lldb-base.cmake
@@ -3,6 +3,7 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON CACHE BOOL "")
 
 set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64 CACHE STRING "")
 set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
+set(LLVM_ENABLE_NO_EXPORTED_SYMBOLS ON CACHE BOOL "")
 
 set(LIBCXX_ENABLE_SHARED OFF CACHE BOOL "")
 set(LIBCXX_ENABLE_STATIC OFF CACHE BOOL "")
diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
index 6f5647d70d8bc1..7e393acacb80d8 100644
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_NO_EXPORTED_SYMBOLS
+  "When building executables, disable any symbol exports (Darwin Only)" OFF)
+
 set(LLVM_CODESIGNING_IDENTITY "" CACHE STRING
   "Sign executables and dylibs with the given identity or skip if empty 
(Darwin Only)")
 
diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
index 745935f1405170..141a97c852e24f 100644
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -258,15 +258,24 @@ if (NOT DEFINED LLVM_LINKER_DETECTED AND NOT WIN32)
 endif()
   endif()
 
-  # Apple's linker complains about duplicate libraries, which CMake likes to do
-  # to support ELF platforms. To silence that warning, we can use
-  # -no_warn_duplicate_libraries, but only in versions of the linker that
-  # support that flag.
-  if(NOT LLVM_USE_LINKER AND ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 include(CheckLinkerFlag)
-check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
-  else()
-set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL "")
+# Linkers that support Darwin allow a setting to internalize all symbol 
exports, 
+# aiding in reducing binary size and often is applicable for executables.
+check_linker_flag(C "-Wl,-no_exported_symbols" 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+
+if (NOT LLVM_USE_LINKER) 
+  # Apple's linker complains about duplicate libraries, which CMake likes 
to do
+  # to support ELF platforms. To silence that warning, we can use
+  # -no_warn_duplicate_libraries, but only in versions of the linker that
+  # support that flag.
+  check_linker_flag(C "-Wl,-no_warn_duplicate_libraries" 
LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES)
+else()
+  set(LLVM_LINKER_SUPPORTS_NO_WARN_DUPLICATE_LIBRARIES OFF CACHE INTERNAL 
"")
+endif()
+  
+  else() 
+set(LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS OFF CACHE INTERNAL "")
   endif()
 endif()
 
@@ -1029,6 +1038,11 @@ macro(add_llvm_executable name)
 add_llvm_symbol_exports( ${name} ${LLVM_EXPORTED_SYMBOL_FILE} )
   endif(LLVM_EXPORTED_SYMBOL_FILE)
 
+  if (LLVM_ENABLE_NO_EXPORTED_SYMBOLS AND 
LLVM_LINKER_SUPPORTS_NO_EXPORTED_SYMBOLS)
+set_property(TARGET ${name} APPEND_STRING PROPERTY
+  LINK_FLAGS " -Wl,-no_exported_symbols")
+  endif()
+
   if (LLVM_LINK_LLVM_DYLIB AND NOT ARG_DISABLE_LLVM_LINK_LLVM_DYLIB)
 set(USE_SHARED USE_SHARED)
   

[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dave Lee via lldb-commits]

kastiglione wrote:

Thanks for adding this! I've been using `CMAKE_EXE_LINKER_FLAGS` to 
`-Wl,-no_exported_symbols`, and have had no problems.

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Dave Lee via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_NO_EXPORTED_SYMBOLS

kastiglione wrote:

should the name reflect the opposite of the default? if so maybe 
`LLVM_DISABLE_EXPORTED_SYMBOLS`?

https://github.com/llvm/llvm-project/pull/87684
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[Lldb-commits] [clang] [lldb] [llvm] [cmake] Build executables with -no_exported_symbols when building Apple toolchain (PR #87684)

[Jon Roelofs via lldb-commits]

@@ -673,6 +673,9 @@ option(LLVM_USE_OPROFILE
 option(LLVM_EXTERNALIZE_DEBUGINFO
   "Generate dSYM files and strip executables and libraries (Darwin Only)" OFF)
 
+option(LLVM_ENABLE_NO_EXPORTED_SYMBOLS

jroelofs wrote:

The double negative is confusing. Maybe invert it, and make the name 
`LLVM_ENABLE_EXPORTED_SYMBOLS`?

https://github.com/llvm/llvm-project/pull/87684
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