From 64a1daed189ab6fff11b33dd8d493962460f0f6c Mon Sep 17 00:00:00 2001 From: John David Anglin Date: Sun, 23 Jul 2017 12:50:44 -0400 Subject: [BZ 19170] Revise comment in sysdeps/hppa/dl-trampoline.S --- sysdeps/hppa/dl-trampoline.S | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'sysdeps/hppa/dl-trampoline.S') diff --git a/sysdeps/hppa/dl-trampoline.S b/sysdeps/hppa/dl-trampoline.S index f1294a931f..3165c6f0e2 100644 --- a/sysdeps/hppa/dl-trampoline.S +++ b/sysdeps/hppa/dl-trampoline.S @@ -82,9 +82,19 @@ _dl_runtime_resolve: bl _dl_fixup,%rp copy %r21,%r19 /* set fixup func ltp */ - /* Sometimes a final executable may attempt to call an undefined - weak function (e.g., __gmon_start__). Return if the function - was not resolved by _dl_fixup */ + /* While the linker will set a function pointer to NULL when it + encounters an undefined weak function, we need to dynamically + detect removed weak functions. The issue arises because a weak + __gmon_start__ function was added to shared executables to work + around issues in _init that are now resolved. The presence of + __gmon_start__ in every shared library breaks the linker + `--as-needed' option. This __gmon_start__ function does nothing + but removal is tricky. Depending on the binding, removal can + cause an application using it to fault. The call to _dl_fixup + returns NULL when a function isn't resolved. In order to help + with __gmon_start__ removal, we return directly to the caller + when _dl_fixup returns NULL. This check could be removed when + BZ 19170 is fixed. */ comib,= 0,%r28,1f /* Load up the returned func descriptor */ -- cgit 1.4.1