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Diffstat (limited to 'contrib/gcc/doc/invoke.texi')
| -rw-r--r-- | contrib/gcc/doc/invoke.texi | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/contrib/gcc/doc/invoke.texi b/contrib/gcc/doc/invoke.texi index 24bf752..165bcc4 100644 --- a/contrib/gcc/doc/invoke.texi +++ b/contrib/gcc/doc/invoke.texi @@ -186,6 +186,7 @@ in the following sections. -frepo -fno-rtti -fstats -ftemplate-depth-@var{n} @gol -fno-threadsafe-statics -fuse-cxa-atexit -fno-weak -nostdinc++ @gol -fno-default-inline -fvisibility-inlines-hidden @gol +-fvisibility-ms-compat @gol -Wabi -Wctor-dtor-privacy @gol -Wnon-virtual-dtor -Wreorder @gol -Weffc++ -Wno-deprecated -Wstrict-null-sentinel @gol @@ -1626,6 +1627,40 @@ Explicitly instantiated inline methods are unaffected by this option as their linkage might otherwise cross a shared library boundary. @xref{Template Instantiation}. +@item -fvisibility-ms-compat +@opindex fvisibility-ms-compat +This flag attempts to use visibility settings to make GCC's C++ +linkage model compatible with that of Microsoft Visual Studio. + +The flag makes these changes to GCC's linkage model: + +@enumerate +@item +It sets the default visibility to @code{hidden}, like +@option{-fvisibility=hidden}. + +@item +Types, but not their members, are not hidden by default. + +@item +The One Definition Rule is relaxed for types without explicit +visibility specifications which are defined in more than one different +shared object: those declarations are permitted if they would have +been permitted when this option was not used. +@end enumerate + +In new code it is better to use @option{-fvisibility=hidden} and +export those classes which are intended to be externally visible. +Unfortunately it is possible for code to rely, perhaps accidentally, +on the Visual Studio behaviour. + +Among the consequences of these changes are that static data members +of the same type with the same name but defined in different shared +objects will be different, so changing one will not change the other; +and that pointers to function members defined in different shared +objects may not compare equal. When this flag is given, it is a +violation of the ODR to define types with the same name differently. + @item -fno-weak @opindex fno-weak Do not use weak symbol support, even if it is provided by the linker. |
