remove LFS64 symbol aliases; replace with dynamic linker remapping

originally the namespace-infringing "large file support" interfaces
were included as part of glibc-ABI-compat, with the intent that they
not be used for linking, since our off_t is and always has been
unconditionally 64-bit and since we usually do not aim to support
nonstandard interfaces when there is an equivalent standard interface.

unfortunately, having the symbols present and available for linking
caused configure scripts to detect them and attempt to use them
without declarations, producing all the expected ill effects that
entails.

as a result, commit 2dd8d5e1b8ba1118ff1782e96545cb8a2318592c was made
to prevent this, using macros to redirect the LFS64 names to the
standard names, conditional on _GNU_SOURCE or _LARGEFILE64_SOURCE.
however, this has turned out to be a source of further problems,
especially since g++ defines _GNU_SOURCE by default. in particular,
the presence of these names as macros breaks a lot of valid code.

this commit removes all the LFS64 symbols and replaces them with a
mechanism in the dynamic linker symbol lookup failure path to retry
with the spurious "64" removed from the symbol name. in the future,
if/when the rest of glibc-ABI-compat is moved out of libc, this can be
removed.

6 files changed, 4 insertions, 14 deletions

diff --git a/compat/time32/__xstat.c b/compat/time32/__xstat.c
index acfbd3cc..e52b5deb 100644
--- a/compat/time32/__xstat.c
+++ b/compat/time32/__xstat.c
@@ -3,22 +3,22 @@
 
 struct stat32;
 
-int __fxstat64(int ver, int fd, struct stat32 *buf)
+int __fxstat(int ver, int fd, struct stat32 *buf)
 {
 	return __fstat_time32(fd, buf);
 }
 
-int __fxstatat64(int ver, int fd, const char *path, struct stat32 *buf, int flag)
+int __fxstatat(int ver, int fd, const char *path, struct stat32 *buf, int flag)
 {
 	return __fstatat_time32(fd, path, buf, flag);
 }
 
-int __lxstat64(int ver, const char *path, struct stat32 *buf)
+int __lxstat(int ver, const char *path, struct stat32 *buf)
 {
 	return __lstat_time32(path, buf);
 }
 
-int __xstat64(int ver, const char *path, struct stat32 *buf)
+int __xstat(int ver, const char *path, struct stat32 *buf)
 {
 	return __stat_time32(path, buf);
 }
diff --git a/compat/time32/aio_suspend_time32.c b/compat/time32/aio_suspend_time32.c
index ed5119bd..d99cb651 100644
--- a/compat/time32/aio_suspend_time32.c
+++ b/compat/time32/aio_suspend_time32.c
@@ -7,5 +7,3 @@ int __aio_suspend_time32(const struct aiocb *const cbs[], int cnt, const struct
 	return aio_suspend(cbs, cnt, ts32 ? (&(struct timespec){
 		.tv_sec = ts32->tv_sec, .tv_nsec = ts32->tv_nsec}) : 0);
 }
-
-weak_alias(aio_suspend, aio_suspend64);
diff --git a/compat/time32/fstat_time32.c b/compat/time32/fstat_time32.c
index 3e084398..e5d52022 100644
--- a/compat/time32/fstat_time32.c
+++ b/compat/time32/fstat_time32.c
@@ -13,5 +13,3 @@ int __fstat_time32(int fd, struct stat32 *restrict st32)
 	if (!r) memcpy(st32, &st, offsetof(struct stat, st_atim));
 	return r;
 }
-
-weak_alias(fstat, fstat64);
diff --git a/compat/time32/fstatat_time32.c b/compat/time32/fstatat_time32.c
index 85dcb008..31d42e63 100644
--- a/compat/time32/fstatat_time32.c
+++ b/compat/time32/fstatat_time32.c
@@ -13,5 +13,3 @@ int __fstatat_time32(int fd, const char *restrict path, struct stat32 *restrict
 	if (!r) memcpy(st32, &st, offsetof(struct stat, st_atim));
 	return r;
 }
-
-weak_alias(fstatat, fstatat64);
diff --git a/compat/time32/lstat_time32.c b/compat/time32/lstat_time32.c
index c1257a14..28cb5a0b 100644
--- a/compat/time32/lstat_time32.c
+++ b/compat/time32/lstat_time32.c
@@ -13,5 +13,3 @@ int __lstat_time32(const char *restrict path, struct stat32 *restrict st32)
 	if (!r) memcpy(st32, &st, offsetof(struct stat, st_atim));
 	return r;
 }
-
-weak_alias(lstat, lstat64);
diff --git a/compat/time32/stat_time32.c b/compat/time32/stat_time32.c
index 8c6121da..b154b0f9 100644
--- a/compat/time32/stat_time32.c
+++ b/compat/time32/stat_time32.c
@@ -13,5 +13,3 @@ int __stat_time32(const char *restrict path, struct stat32 *restrict st32)
 	if (!r) memcpy(st32, &st, offsetof(struct stat, st_atim));
 	return r;
 }
-
-weak_alias(stat, stat64);