lib: Add the needed bits for compiling with link-time optimization.

GCC 10.2 and LLVM/Clang 10 offer initial support for building libraries, that are using symbol versioning features, with LTO. To make use of this, the exported versioned symbols need their visibility attributes declared explicitly. Fixes #24.
besser82 · Aug 13, 2020 · 1b1baee · 1b1baee
1 parent e9a6b2d
commit 1b1baee
Show file tree

Hide file tree

Showing 5 changed files with 36 additions and 0 deletions.
diff --git a/lib/crypt-des-obsolete.c b/lib/crypt-des-obsolete.c
@@ -121,6 +121,7 @@ do_setkey_r (const char *key, struct des_ctx *ctx)
 #endif
 
 #if INCLUDE_setkey_r
+xcrypt_symbol
 void
 setkey_r (ARG_UNUSED (const char *key), ARG_UNUSED (struct crypt_data *data))
 {
@@ -148,6 +149,7 @@ do_encrypt_r (char *block, int edflag, struct des_ctx *ctx)
 #endif
 
 #if INCLUDE_encrypt_r
+xcrypt_symbol
 void
 encrypt_r (char *block, ARG_UNUSED (int edflag),
            ARG_UNUSED (struct crypt_data *data))
@@ -180,6 +182,7 @@ static struct des_ctx nr_encrypt_ctx;
 #endif
 
 #if INCLUDE_setkey
+xcrypt_symbol
 void
 setkey (ARG_UNUSED (const char *key))
 {
@@ -194,6 +197,7 @@ SYMVER_setkey;
 #endif
 
 #if INCLUDE_encrypt
+xcrypt_symbol
 void
 encrypt (char *block, ARG_UNUSED (int edflag))
 {

diff --git a/lib/crypt-gensalt-static.c b/lib/crypt-gensalt-static.c
@@ -22,6 +22,7 @@
    will not have the state objects in its data segment.  */
 
 #if INCLUDE_crypt_gensalt
+xcrypt_symbol
 char *
 crypt_gensalt (const char *prefix, unsigned long count,
                const char *rbytes, int nrbytes)
@@ -36,6 +37,7 @@ SYMVER_crypt_gensalt;
 
 /* For code compatibility with older versions (v3.1.1 and earlier).  */
 #if INCLUDE_crypt_gensalt && INCLUDE_xcrypt_gensalt
+xcrypt_symbol
 strong_alias (crypt_gensalt, xcrypt_gensalt);
 SYMVER_xcrypt_gensalt;
 #endif
diff --git a/lib/crypt-port.h b/lib/crypt-port.h
@@ -161,6 +161,22 @@ _crypt_strcpy_or_abort (void *, const size_t, const void *);
 /* Define ALIASNAME as a strong alias for NAME.  */
 #define strong_alias(name, aliasname) _strong_alias(name, aliasname)
 
+/* Define a symbol to be external visible.  */
+#if (defined __GNUC__ && __GNUC__ >= 5) && !defined __clang__
+
+# define xcrypt_symbol                                           \
+  __attribute__((visibility("default"), externally_visible))
+
+#elif defined __GNUC__ && __GNUC__ >= 3
+
+# define xcrypt_symbol                       \
+  __attribute__((visibility("default")))
+
+#else
+
+# define xcrypt_symbol
+
+#endif
 /* Darwin (Mach-O) doesn't support alias attributes or symbol versioning.
    It does, however, support symbol aliasing at the object file level.  */
 #ifdef __APPLE__

diff --git a/lib/crypt-static.c b/lib/crypt-static.c
@@ -24,6 +24,7 @@
    will not have the state objects in its data segment.  */
 
 #if INCLUDE_crypt || INCLUDE_fcrypt
+xcrypt_symbol
 char *
 crypt (const char *key, const char *setting)
 {
@@ -38,6 +39,7 @@ SYMVER_crypt;
 
 #if INCLUDE_fcrypt
 #if ENABLE_OBSOLETE_API_ENOSYS
+xcrypt_symbol
 char *
 fcrypt (ARG_UNUSED (const char *key), ARG_UNUSED (const char *setting))
 {
@@ -54,13 +56,15 @@ fcrypt (ARG_UNUSED (const char *key), ARG_UNUSED (const char *setting))
 #endif
 }
 #else
+xcrypt_symbol
 strong_alias (crypt, fcrypt);
 #endif
 SYMVER_fcrypt;
 #endif
 
 /* For code compatibility with older versions (v3.1.1 and earlier).  */
 #if INCLUDE_crypt && INCLUDE_xcrypt
+xcrypt_symbol
 strong_alias (crypt, xcrypt);
 SYMVER_xcrypt;
 #endif
diff --git a/lib/crypt.c b/lib/crypt.c
@@ -145,6 +145,7 @@ do_crypt (const char *phrase, const char *setting, struct crypt_data *data)
 }
 
 #if INCLUDE_crypt_rn
+xcrypt_symbol
 char *
 crypt_rn (const char *phrase, const char *setting, void *data, int size)
 {
@@ -163,6 +164,7 @@ SYMVER_crypt_rn;
 #endif
 
 #if INCLUDE_crypt_ra
+xcrypt_symbol
 char *
 crypt_ra (const char *phrase, const char *setting, void **data, int *size)
 {
@@ -191,6 +193,7 @@ SYMVER_crypt_ra;
 #endif
 
 #if INCLUDE_crypt_r
+xcrypt_symbol
 char *
 crypt_r (const char *phrase, const char *setting, struct crypt_data *data)
 {
@@ -207,11 +210,13 @@ SYMVER_crypt_r;
 
 /* For code compatibility with older versions (v3.1.1 and earlier).  */
 #if INCLUDE_crypt_r && INCLUDE_xcrypt_r
+xcrypt_symbol
 strong_alias (crypt_r, xcrypt_r);
 SYMVER_xcrypt_r;
 #endif
 
 #if INCLUDE_crypt_gensalt_rn
+xcrypt_symbol
 char *
 crypt_gensalt_rn (const char *prefix, unsigned long count,
                   const char *rbytes, int nrbytes, char *output,
@@ -279,17 +284,20 @@ SYMVER_crypt_gensalt_rn;
 
 /* For code compatibility with older versions (v3.1.1 and earlier).  */
 #if INCLUDE_crypt_gensalt_rn && INCLUDE_crypt_gensalt_r
+xcrypt_symbol
 strong_alias (crypt_gensalt_rn, crypt_gensalt_r);
 SYMVER_crypt_gensalt_r;
 #endif
 
 /* For code compatibility with older versions (v3.1.1 and earlier).  */
 #if INCLUDE_crypt_gensalt_rn && INCLUDE_xcrypt_gensalt_r
+xcrypt_symbol
 strong_alias (crypt_gensalt_rn, xcrypt_gensalt_r);
 SYMVER_xcrypt_gensalt_r;
 #endif
 
 #if INCLUDE_crypt_gensalt_ra
+xcrypt_symbol
 char *
 crypt_gensalt_ra (const char *prefix, unsigned long count,
                   const char *rbytes, int nrbytes)
@@ -310,6 +318,7 @@ SYMVER_crypt_gensalt_ra;
 #if INCLUDE_crypt_checksalt
 static_assert(CRYPT_SALT_OK == 0, "CRYPT_SALT_OK does not equal zero");
 
+xcrypt_symbol
 int
 crypt_checksalt (const char *setting)
 {
@@ -329,6 +338,7 @@ SYMVER_crypt_checksalt;
 #endif
 
 #if INCLUDE_crypt_preferred_method
+xcrypt_symbol
 const char *
 crypt_preferred_method (void)
 {