Bug #25835560: SET DEFAULT SYMBOL VISIBILITY TO HIDDEN

Hide all symbols by default and export only the ones that are supposed to actually be visible. This primarily affects mysqld, but also plugins and statically linked libraries of various sorts now stop polluting the server's namespace. In addition, we export 297 “legacy” functions and classes that were already in use by existing plugins; this is not meant as an endorsement of the practice, and is likely to break in the future, but fixing them all is a longer procedure that will take time. A stripped mysqld binary (RelWithDebInfo) on Linux goes from 38 to 34 MB, exporting 950 instead of 20854 symbols. Windows builds can now skip the WScript step that goes through every symbol and exports it manually through a .def file. On a 16-core Xeon build server (vale31), this reduces the build time of a full debug build by about 40 seconds (from 9 minutes 25 seconds to 8 minutes 45 seconds). The difference for an incremental build, ie., just touching sql/main.cc and rebuilding, is even bigger; it goes from 1m42s to just under 13 seconds, as the incrementality is significantly increased. Change-Id: I2d1c39b6822502139e3286c7473db81c876b7bbc
polardb · Apr 7, 2017 · bc4eff8 · bc4eff8
1 parent e4103ba
commit bc4eff8
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Showing 226 changed files with 1,686 additions and 1,529 deletions.
diff --git a/cmake/build_configurations/compiler_options.cmake b/cmake/build_configurations/compiler_options.cmake
@@ -30,7 +30,7 @@ IF(UNIX)
 
   # Default GCC flags
   IF(CMAKE_COMPILER_IS_GNUCC)
-    SET(COMMON_C_FLAGS               "-g -fno-omit-frame-pointer")
+    SET(COMMON_C_FLAGS               "-g -fno-omit-frame-pointer -fvisibility=hidden")
     # Disable inline optimizations for valgrind testing to avoid false positives
     IF(WITH_VALGRIND)
       SET(COMMON_C_FLAGS             "-fno-inline ${COMMON_C_FLAGS}")
@@ -46,7 +46,7 @@ IF(UNIX)
     SET(CMAKE_C_FLAGS_RELWITHDEBINFO "-O3 ${COMMON_C_FLAGS}")
   ENDIF()
   IF(CMAKE_COMPILER_IS_GNUCXX)
-    SET(COMMON_CXX_FLAGS               "-g -fno-omit-frame-pointer -std=c++11")
+    SET(COMMON_CXX_FLAGS               "-g -fno-omit-frame-pointer -std=c++11 -fvisibility=hidden")
     # Disable inline optimizations for valgrind testing to avoid false positives
     IF(WITH_VALGRIND)
       SET(COMMON_CXX_FLAGS             "-fno-inline ${COMMON_CXX_FLAGS}")
@@ -66,15 +66,15 @@ IF(UNIX)
 
   # Default Clang flags
   IF(CMAKE_C_COMPILER_ID MATCHES "Clang")
-    SET(COMMON_C_FLAGS               "-g -fno-omit-frame-pointer")
+    SET(COMMON_C_FLAGS               "-g -fno-omit-frame-pointer -fvisibility=hidden")
     IF(NOT DISABLE_SHARED)
       SET(COMMON_C_FLAGS             "-fPIC ${COMMON_C_FLAGS}")
     ENDIF()
     SET(CMAKE_C_FLAGS_DEBUG          "${COMMON_C_FLAGS}")
     SET(CMAKE_C_FLAGS_RELWITHDEBINFO "-O3 ${COMMON_C_FLAGS}")
   ENDIF()
   IF(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-    SET(COMMON_CXX_FLAGS               "-g -fno-omit-frame-pointer -std=c++11")
+    SET(COMMON_CXX_FLAGS               "-g -fno-omit-frame-pointer -std=c++11 -fvisibility=hidden")
     IF(NOT DISABLE_SHARED)
       SET(COMMON_CXX_FLAGS             "-fPIC ${COMMON_CXX_FLAGS}")
     ENDIF()
@@ -109,6 +109,7 @@ IF(UNIX)
       SET(SUNPRO_FLAGS     "-xdebuginfo=no%decl")
       SET(SUNPRO_FLAGS     "${SUNPRO_FLAGS} -xbuiltin=%all")
       SET(SUNPRO_FLAGS     "${SUNPRO_FLAGS} -xlibmil")
+      SET(SUNPRO_FLAGS     "${SUNPRO_FLAGS} -xldscope=symbolic")
       IF(NOT DISABLE_SHARED)
         SET(SUNPRO_FLAGS   "${SUNPRO_FLAGS} -KPIC")
       ENDIF()

diff --git a/cmake/os/Windows.cmake b/cmake/os/Windows.cmake
@@ -129,6 +129,14 @@ IF(MSVC)
   #TODO: update the code and remove the disabled warnings
   SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /wd4800 /wd4805 /wd4996")
   SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /wd4800 /wd4805 /wd4996 /we4099")
+
+  # These are warnings about exported entry points not being complete,
+  # e.g. exporting "Baz *Foo::bar();" without Baz being exported.
+  # As most of these are for legacy export (MYSQL_PLUGIN_LEGACY_API),
+  # we deliberately keep the exported interface minimal, and thus,
+  # we suppress these warnings.
+  SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /wd4251 /wd4275")
+  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /wd4251 /wd4275")
 ENDIF()
 
 # Always link with socket library

diff --git a/cmake/plugin.cmake b/cmake/plugin.cmake
@@ -120,8 +120,16 @@ MACRO(MYSQL_ADD_PLUGIN)
   # Build either static library or module
   IF (WITH_${plugin} AND NOT ARG_MODULE_ONLY)
     ADD_CONVENIENCE_LIBRARY(${target} STATIC ${SOURCES})
+
+    # Plugins are taken to be part of the server (so MYSQL_SERVER).
+    # However, also make sure that when building the plugin statically, we
+    # don't try to export any symbols pulled in from header files.
+    # This would be harmless in the server, but some of the statically linked
+    # plugins (like the performance schema plugin) are also linked into unit
+    # tests, which don't necessarily link in all the dependencies of such
+    # symbols.
     SET_TARGET_PROPERTIES(${target}
-      PROPERTIES COMPILE_DEFINITIONS "MYSQL_SERVER")
+      PROPERTIES COMPILE_DEFINITIONS "MYSQL_SERVER;MYSQL_NO_PLUGIN_EXPORT")
     SET_TARGET_PROPERTIES(${target}
       PROPERTIES COMPILE_FLAGS ${SSL_DEFINES})
 
@@ -132,9 +140,9 @@ MACRO(MYSQL_ADD_PLUGIN)
       OUTPUT_NAME ${ARG_STATIC_OUTPUT_NAME})
     ENDIF()
 
-    # Update mysqld dependencies
-    SET (MYSQLD_STATIC_PLUGIN_LIBS ${MYSQLD_STATIC_PLUGIN_LIBS} 
-      ${target} ${ARG_LINK_LIBRARIES} CACHE INTERNAL "" FORCE)
+    # Link the plugin into mysqld.
+    SET (MYSQLD_STATIC_PLUGIN_LIBS ${MYSQLD_STATIC_PLUGIN_LIBS}
+       ${target} CACHE INTERNAL "" FORCE)
 
     IF(ARG_MANDATORY)
       SET(${with_var} ON CACHE INTERNAL "Link ${plugin} statically to the server" 
@@ -178,19 +186,19 @@ MACRO(MYSQL_ADD_PLUGIN)
     # unresolved symbols. Others are less strict and allow unresolved symbols
     # in shared libraries. On Linux for example, CMake does not even add 
     # executable to the linker command line (it would result into link error). 
-    # Thus we skip TARGET_LINK_LIBRARIES on Linux, as it would only generate
-    # an additional dependency.
-    # Use MYSQL_PLUGIN_IMPORT for static data symbols to be exported.
+    # Use MYSQL_PLUGIN_API for symbols to be exported/imported.
     IF(WIN32 OR APPLE)
       TARGET_LINK_LIBRARIES (${target} mysqld ${ARG_LINK_LIBRARIES})
+    ELSE()
+      TARGET_LINK_LIBRARIES (${target} ${ARG_LINK_LIBRARIES})
     ENDIF()
     ADD_DEPENDENCIES(${target} GenError ${ARG_DEPENDENCIES})
 
-     IF(NOT ARG_MODULE_ONLY)
+    IF(NOT ARG_MODULE_ONLY)
       # set cached variable, e.g with checkbox in GUI
       SET(${with_var} OFF CACHE BOOL "Link ${plugin} statically to the server" 
        FORCE)
-     ENDIF()
+    ENDIF()
     SET_TARGET_PROPERTIES(${target} PROPERTIES 
       OUTPUT_NAME "${ARG_MODULE_OUTPUT_NAME}")  
 

diff --git a/components/mysql_server/dynamic_loader_path_filter.cc b/components/mysql_server/dynamic_loader_path_filter.cc
@@ -28,7 +28,7 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02111-1307  USA */
 
 typedef std::string my_string;
 
-extern "C" MYSQL_PLUGIN_IMPORT CHARSET_INFO *system_charset_info;
+extern "C" MYSQL_PLUGIN_API CHARSET_INFO *system_charset_info;
 bool check_string_char_length(const LEX_CSTRING &str, const char *err_msg,
   size_t max_char_length, const CHARSET_INFO *cs,
   bool no_error);

diff --git a/configure.cmake b/configure.cmake
@@ -519,9 +519,6 @@ ENDIF()
 
 SET(CMAKE_EXTRA_INCLUDE_FILES)
 
-# Support for tagging symbols with __attribute__((visibility("hidden")))
-MY_CHECK_CXX_COMPILER_FLAG("-fvisibility=hidden" HAVE_VISIBILITY_HIDDEN)
-
 #
 # Code tests
 #

diff --git a/dbug/dbug.c b/dbug/dbug.c
@@ -96,6 +96,7 @@
 #include "my_inttypes.h"
 #include "my_io.h"
 #include "my_macros.h"
+#include "my_sharedlib.h"
 #include "my_sys.h"
 #include "my_thread_local.h"
 #include "mysql/service_my_snprintf.h"
@@ -402,7 +403,7 @@ static void unlock_stack(CODE_STATE *cs)
  *
  */
 
-void _db_process_(const char *name)
+void MYSQL_PLUGIN_API _db_process_(const char *name)
 {
   CODE_STATE *cs;
 
@@ -840,7 +841,7 @@ static void FixTraceFlags(uint old_fflags, CODE_STATE *cs)
  *
  */
 
-void _db_set_(const char *control)
+MYSQL_PLUGIN_API void _db_set_(const char *control)
 {
   CODE_STATE *cs;
   uint old_fflags;
@@ -879,7 +880,7 @@ void _db_set_(const char *control)
  *
  */
 
-void _db_push_(const char *control)
+MYSQL_PLUGIN_API void _db_push_(const char *control)
 {
   CODE_STATE *cs;
   uint old_fflags;
@@ -904,7 +905,7 @@ void _db_push_(const char *control)
   Returns TRUE if session-local settings have been set.
 */
 
-int _db_is_pushed_()
+MYSQL_PLUGIN_API int _db_is_pushed_()
 {
   CODE_STATE *cs= NULL;
   get_code_state_or_return FALSE;
@@ -926,7 +927,7 @@ int _db_is_pushed_()
  *
  */
 
-void _db_set_init_(const char *control)
+MYSQL_PLUGIN_API void _db_set_init_(const char *control)
 {
   CODE_STATE tmp_cs;
   memset(&tmp_cs, 0, sizeof(tmp_cs));
@@ -952,7 +953,7 @@ void _db_set_init_(const char *control)
  *
  */
 
-void _db_pop_()
+MYSQL_PLUGIN_API void _db_pop_()
 {
   struct settings *discard;
   uint old_fflags;
@@ -1068,7 +1069,7 @@ void _db_pop_()
         }                                       \
       } while (0)
 
-int _db_explain_ (CODE_STATE *cs, char *buf, size_t len)
+MYSQL_PLUGIN_API int _db_explain_ (CODE_STATE *cs, char *buf, size_t len)
 {
   char *start=buf, *end=buf+len-4;
 
@@ -1172,8 +1173,9 @@ int _db_explain_init_(char *buf, size_t len)
  *
  */
 
-void _db_enter_(const char *_func_, const char *_file_,
-                uint _line_, struct _db_stack_frame_ *_stack_frame_)
+MYSQL_PLUGIN_API void _db_enter_(
+  const char *_func_, const char *_file_,
+  uint _line_, struct _db_stack_frame_ *_stack_frame_)
 {
   int save_errno;
   CODE_STATE *cs;
@@ -1242,7 +1244,8 @@ void _db_enter_(const char *_func_, const char *_file_,
  *
  */
 
-void _db_return_(uint _line_, struct _db_stack_frame_ *_stack_frame_)
+MYSQL_PLUGIN_API void _db_return_(
+  uint _line_, struct _db_stack_frame_ *_stack_frame_)
 {
   int save_errno=errno;
   uint _slevel_= _stack_frame_->level & ~TRACE_ON;
@@ -1305,7 +1308,7 @@ void _db_return_(uint _line_, struct _db_stack_frame_ *_stack_frame_)
  *
  */
 
-void _db_pargs_(uint _line_, const char *keyword)
+MYSQL_PLUGIN_API void _db_pargs_(uint _line_, const char *keyword)
 {
   CODE_STATE *cs;
   get_code_state_or_return;
@@ -1331,7 +1334,7 @@ void _db_pargs_(uint _line_, const char *keyword)
  *    function evaluates to 1.
  */
 
-int _db_enabled_()
+MYSQL_PLUGIN_API int _db_enabled_()
 {
   CODE_STATE *cs;
 
@@ -1370,7 +1373,7 @@ int _db_enabled_()
 
 #include <stdarg.h>
 
-void _db_doprnt_(const char *format,...)
+MYSQL_PLUGIN_API void _db_doprnt_(const char *format,...)
 {
   va_list args;
   CODE_STATE *cs;
@@ -1433,7 +1436,7 @@ static void DbugVfprintf(FILE *stream, const char* format, va_list args)
  *  Is used to examine corrupted memory or arrays.
  */
 
-void _db_dump_(uint _line_, const char *keyword,
+MYSQL_PLUGIN_API void _db_dump_(uint _line_, const char *keyword,
                const unsigned char *memory, size_t length)
 {
   int pos;
@@ -1764,7 +1767,7 @@ static void FreeState(CODE_STATE *cs, struct settings *state, int free_state)
  *	To be called at the very end of the program.
  *
  */
-void _db_end_()
+MYSQL_PLUGIN_API void _db_end_()
 {
   struct settings *discard;
   static struct settings tmp;
@@ -1865,7 +1868,7 @@ FILE *_db_fp_(void)
  *
  */
 
-int _db_keyword_(CODE_STATE *cs, const char *keyword, int strict)
+MYSQL_PLUGIN_API int _db_keyword_(CODE_STATE *cs, const char *keyword, int strict)
 {
   bool result;
   get_code_state_if_not_set_or_return FALSE;
@@ -2283,7 +2286,7 @@ static void DbugFlush(CODE_STATE *cs)
 
 /* For debugging */
 
-void _db_flush_()
+MYSQL_PLUGIN_API void _db_flush_()
 {
   CODE_STATE *cs= NULL;
   get_code_state_or_return;
@@ -2297,7 +2300,7 @@ void _db_flush_()
 extern void __gcov_flush();
 #endif
 
-void _db_flush_gcov_()
+MYSQL_PLUGIN_API void _db_flush_gcov_()
 {
 #ifdef HAVE_GCOV
   // Gcov will assert() if we try to flush in parallel.
@@ -2307,7 +2310,7 @@ void _db_flush_gcov_()
 #endif
 }
 
-void _db_suicide_()
+MYSQL_PLUGIN_API void _db_suicide_()
 {
   int retval;
   sigset_t new_mask;
@@ -2332,23 +2335,23 @@ void _db_suicide_()
 #endif  /* ! _WIN32 */
 
 
-void _db_lock_file_()
+MYSQL_PLUGIN_API void _db_lock_file_()
 {
   CODE_STATE *cs;
   get_code_state_or_return;
   native_mutex_lock(&THR_LOCK_dbug);
   cs->locked=1;
 }
 
-void _db_unlock_file_()
+MYSQL_PLUGIN_API void _db_unlock_file_()
 {
   CODE_STATE *cs;
   get_code_state_or_return;
   cs->locked=0;
   native_mutex_unlock(&THR_LOCK_dbug);
 }
 
-const char* _db_get_func_(void)
+MYSQL_PLUGIN_API const char* _db_get_func_(void)
 {
   CODE_STATE *cs;
   get_code_state_or_return NULL;

diff --git a/extra/regex/my_regex.h b/extra/regex/my_regex.h
@@ -4,6 +4,7 @@
 /* ========= begin header generated by ./mkh ========= */
 
 #include "m_ctype.h"
+#include "my_sharedlib.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -31,8 +32,8 @@ typedef struct {
 
 /* === regcomp.c === */
 typedef int (*my_regex_stack_check_t)(int);
-extern int my_regcomp(my_regex_t *, const char *, int,
-                      const CHARSET_INFO *charset);
+extern MYSQL_PLUGIN_LEGACY_API int my_regcomp(
+  my_regex_t *, const char *, int, const CHARSET_INFO *charset);
 #define	MY_REG_BASIC	0000
 #define	MY_REG_EXTENDED	0001
 #define	MY_REG_ICASE	0002
@@ -66,7 +67,8 @@ extern size_t my_regerror(int, const my_regex_t *, char *, size_t);
 
 
 /* === regexec.c === */
-extern int my_regexec(const my_regex_t *, const char *, size_t, my_regmatch_t [], int);
+extern MYSQL_PLUGIN_LEGACY_API int my_regexec(
+  const my_regex_t *, const char *, size_t, my_regmatch_t [], int);
 #define	MY_REG_NOTBOL	00001
 #define	MY_REG_NOTEOL	00002
 #define	MY_REG_STARTEND	00004
@@ -76,14 +78,14 @@ extern int my_regexec(const my_regex_t *, const char *, size_t, my_regmatch_t []
 
 
 /* === regfree.c === */
-extern void my_regfree(my_regex_t *);
+extern MYSQL_PLUGIN_LEGACY_API void my_regfree(my_regex_t *);
 
 /* === reginit.c === */
 
 /* Should be called for multithread progs */
 extern void my_regex_init(const CHARSET_INFO *cs,
                           my_regex_stack_check_t func);
-extern void my_regex_end(void);	/* If one wants a clean end */
+extern MYSQL_PLUGIN_LEGACY_API void my_regex_end(void);	/* If one wants a clean end */
 
 #ifdef __cplusplus
 }

diff --git a/extra/regex/regcomp.c b/extra/regex/regcomp.c
@@ -112,7 +112,7 @@ static int never = 0;		/* for use in asserts; shuts lint up */
  = #define	MY_REG_PEND	0040
  = #define	MY_REG_DUMP	0200
  */
-int				/* 0 success, otherwise MY_REG_something */
+MYSQL_PLUGIN_LEGACY_API int		/* 0 success, otherwise MY_REG_something */
 my_regcomp(preg, pattern, cflags, charset)
 my_regex_t *preg;
 const char *pattern;

diff --git a/extra/regex/regexec.c b/extra/regex/regexec.c
@@ -138,7 +138,7 @@
 
   @return 0 success, MY_REG_NOMATCH failure
  */
-int
+MYSQL_PLUGIN_LEGACY_API int
 my_regexec(preg, str, nmatch, pmatch, eflags)
 const my_regex_t *preg;
 const char *str;