[libcxx-commits] [libcxx] 308a5b1 - [libc++] Inlines format_error for clang-cl DLL.

[Mark de Wever via libcxx-commits]

Author: Mark de Wever
Date: 2022-08-31T19:13:19+02:00
New Revision: 308a5b1a32f0ff795cbe4115bec447c56c77617a

URL: https://github.com/llvm/llvm-project/commit/308a5b1a32f0ff795cbe4115bec447c56c77617a
DIFF: https://github.com/llvm/llvm-project/commit/308a5b1a32f0ff795cbe4115bec447c56c77617a.diff

LOG: [libc++] Inlines format_error for clang-cl DLL.

This version is build without support for the experimental library but
the code still wants to link this function. Inlining the function solves
the issue.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D132667

Added: 
    

Modified: 
    libcxx/CMakeLists.txt
    libcxx/include/__format/format_error.h
    libcxx/src/format.cpp

Removed: 
    


################################################################################
diff  --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index aeaf6b062472a..9cad2394178dc 100644
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -832,6 +832,14 @@ function(cxx_add_windows_flags target)
                                  # Use the ISO conforming behaviour for conversion
                                  # in printf, scanf.
                                  _CRT_STDIO_ISO_WIDE_SPECIFIERS)
+    # Clang-cl shared builds don't support the experimental library.
+    # To avoid linker errors the format_error destructor is inlined for the
+    # dylib. Users can never use format in this mode.
+    # TODO FMT Remove when format becomes mainline.
+    if (LIBCXX_ENABLE_SHARED)
+      target_compile_definitions(${target} PRIVATE
+                                 _LIBCPP_INLINE_FORMAT_ERROR_DTOR)
+    endif()
   endif()
 endfunction()
 

diff  --git a/libcxx/include/__format/format_error.h b/libcxx/include/__format/format_error.h
index 2ca527279e0b8..742b654686ac1 100644
--- a/libcxx/include/__format/format_error.h
+++ b/libcxx/include/__format/format_error.h
@@ -31,7 +31,14 @@ class _LIBCPP_EXCEPTION_ABI format_error : public runtime_error {
       : runtime_error(__s) {}
   _LIBCPP_HIDE_FROM_ABI explicit format_error(const char* __s)
       : runtime_error(__s) {}
+  // TODO FMT Remove when format is no longer experimental.
+  // Avoids linker errors when building the Clang-cl Windows DLL which doesn't
+  // support the experimental library.
+#  ifndef _LIBCPP_INLINE_FORMAT_ERROR_DTOR
   ~format_error() noexcept override;
+#  else
+  ~format_error() noexcept  override {}
+#  endif
 };
 
 _LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void

diff  --git a/libcxx/src/format.cpp b/libcxx/src/format.cpp
index cdbcbf8b058d2..401cccf17210a 100644
--- a/libcxx/src/format.cpp
+++ b/libcxx/src/format.cpp
@@ -10,6 +10,8 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
+#ifndef _LIBCPP_INLINE_FORMAT_ERROR_DTOR
 format_error::~format_error() noexcept = default;
+#endif
 
 _LIBCPP_END_NAMESPACE_STD