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Diffstat (limited to 'gcc/doc/invoke.texi')
| -rw-r--r-- | gcc/doc/invoke.texi | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 92cc25002a3..14955dd1be0 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -191,6 +191,8 @@ in the following sections. -ftemplate-depth=@var{n} @gol -fno-threadsafe-statics -fuse-cxa-atexit -fno-weak -nostdinc++ @gol -fno-default-inline -fvisibility-inlines-hidden @gol +-fvtable-verify=@var{std|preinit|none} @gol +-fvtv-counts -fvtv-debug @gol -fvisibility-ms-compat @gol -fext-numeric-literals @gol -Wabi -Wconversion-null -Wctor-dtor-privacy @gol @@ -318,6 +320,7 @@ Objective-C and Objective-C++ Dialects}. -fdump-tree-sra@r{[}-@var{n}@r{]} @gol -fdump-tree-forwprop@r{[}-@var{n}@r{]} @gol -fdump-tree-fre@r{[}-@var{n}@r{]} @gol +-fdump-tree-vtable-verify @gol -fdump-tree-vrp@r{[}-@var{n}@r{]} @gol -ftree-vectorizer-verbose=@var{n} @gol -fdump-tree-storeccp@r{[}-@var{n}@r{]} @gol @@ -2302,6 +2305,56 @@ 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 -fvtable-verify=@var{std|preinit|none} +@opindex fvtable-verify +Turn on (or off, if using @option{-fvtable-verify=none}) the security +feature that verifies at runtime, for every virtual call that is made, that +the vtable pointer through which the call is made is valid for the type of +the object, and has not been corrupted or overwritten. If an invalid vtable +pointer is detected (at runtime), an error is reported and execution of the +program is immediately halted. + +This option causes runtime data structures to be built, at program start up, +for verifying the vtable pointers. The options @code{std} and @code{preinit} +control the timing of when these data structures are built. In both cases the +data structures are built before execution reaches 'main'. The +@option{-fvtable-verify=std} causes these data structure to be built after the +shared libraries have been loaded and initialized. +@option{-fvtable-verify=preinit} causes them to be built before the shared +libraries have been loaded and initialized. + +If this option appears multiple times in the compiler line, with different +values specified, 'none' will take highest priority over both 'std' and +'preinit'; 'preinit' will take priority over 'std'. + +@item -fvtv-debug +@opindex (fvtv-debug) +Causes debug versions of the runtime functions for the vtable verification +feature to be called. This assumes the @option{-fvtable-verify=std} or +@option{-fvtable-verify=preinit} has been used. This flag will also cause the +compiler to keep track of which vtable pointers it found for each class, and +record that information in the file ``vtv_set_ptr_data.log'', in the dump +file directory on the user's machine. + +Note: This feature APPENDS data to the log file. If you want a fresh log +file, be sure to delete any existing one. + +@item -fvtv-counts +@opindex (fvtv-counts) +This is a debugging flag. When used in conjunction with +@option{-fvtable-verify=std} or @option{-fvtable-verify=preinit}, this +causes the compiler to keep track of the total number of virtual calls +it encountered and the number of verifications it inserted. It also +counts the number of calls to certain runtime library functions +that it inserts. This information, for each compilation unit, is written +to a file named ``vtv_count_data.log'', in the dump_file directory on +the user's machine. It also counts the size of the vtable pointer sets +for each class, and writes this information to ``vtv_class_set_sizes.log'' +in the same directory. + +Note: This feature APPENDS data to the log files. To get a fresh log +files, be sure to delete any existing ones. + @item -fno-weak @opindex fno-weak Do not use weak symbol support, even if it is provided by the linker. |