[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 --- Comment #13 from David Vitek --- Created attachment 43639 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43639=edit hack for g++4.5.3 and old libc compatibility This is a nasty hack and you should check that your system's definition of PTHREAD_COND_INITIALIZER is all zeroes before using it.
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 --- Comment #12 from David Vitek --- Created attachment 43638 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43638=edit patch for g++7.3 and old libc This patch fixes the parse error with newer versions of g++
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907
David Vitek changed:
What|Removed |Added
CC||dvitek at grammatech dot com
--- Comment #11 from David Vitek ---
I ran into this and figured out a solution. There are actually two different
issues at play depending on which version of g++ is trying to build rwlock.cc.
g++ 7.3 can't deal with PTHREAD_COND_INITIALIZER being surrounded by parens in
the initializer list. If we take away the parens, it parses great with g++
7.3. I suspect this could be fixed in version control. Specifically, the
string literal in the older definition of PTHREAD_COND_INITIALIZER does not
want to be converted to a character array.
g++ 4.5.3 refuses to parse any formulation I've been able to think of unless I
make the initializer list completely empty. It just so happens that
PTHREAD_COND_INITIALIZER is a zero initializer with my libc, so the empty
initializer list is sufficient but abstraction-breaking. You couldn't safely
commit this workaround to version control.
Details:
PTHREAD_COND_INITIALIZER expands to {{ 0, 0 }, 0, "", 0}
Here is the definition of pthread_cond_t:
struct _pthread_fastlock
{
long int __status;
int __spinlock;
};
typedef struct _pthread_descr_struct *_pthread_descr;
__extension__ typedef long long __pthread_cond_align_t;
typedef struct
{
struct _pthread_fastlock __c_lock;
_pthread_descr __c_waiting;
char __padding[48 - sizeof (struct _pthread_fastlock)
- sizeof (_pthread_descr) - sizeof (__pthread_cond_align_t)];
__pthread_cond_align_t __align;
} pthread_cond_t;
struct S{
pthread_cond_t x;
/* g++ 7.3: error: no matching function for call to
'pthread_cond_t::pthread_cond_t()'
* g++ 4.5.3: error: could not convert '{{0, 0}, 0, "", 0}' to
'pthread_cond_t'
*/
S() : x (PTHREAD_COND_INITIALIZER) {}
};
// Now without the parens:
struct S{
pthread_cond_t x;
/* g++ 7.3: Success!
* g++ 4.5.3: error: could not convert '{{0, 0}, 0, "", 0}' to
'pthread_cond_t'
*/
S() : x PTHREAD_COND_INITIALIZER {}
};
Here are some stand-alone diagnostics that elucidate the root cause:
g++ 4.5.3 can't handle this code even with -std=gnu++0x. I wasn't able to come
up with anything viable here besides {}.
struct S{
struct inner{
char A[1];
} x;
/* could not convert '{{0}}' to 'S::inner' */
S() : x {{0}} {};
};
g++ 7.3 doesn't like this:
struct R{
struct inner{
char __padding[1];
} x;
/* error: no matching function for call to 'R::inner::inner()' */
R() : x ({""}) {};
};
but it does like this:
struct R{
struct inner{
char __padding[1];
} x;
// OK
R() : x {""} {};
};
Two patches forthcoming...
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 --- Comment #10 from Klaus Rudolph --- Created attachment 39830 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39830=edit preprocessed file rwlock.ii Add rwlock.ii file as requested.
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 --- Comment #9 from Klaus Rudolph --- hi all, > Gesendet: Freitag, 14. Oktober 2016 um 10:32 Uhr > Von: "redi at gcc dot gnu.org" <gcc-bugzi...@gcc.gnu.org> > An: lts-rudo...@gmx.de > Betreff: [Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile > > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 > > --- Comment #6 from Jonathan Wakely --- > See https://gcc.gnu.org/bugs/ > How can I add "-save-temps" to the gcc build process itself. Because the bug is compiling the libitm library from the compiler compilation itself. Anything which can be done with "./configure" or must the Makefiles be patched? I have no idea how to set this additional CFLAG/CXXFLAG or similar. Regards Klaus
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 --- Comment #8 from Andrew Pinski --- (In reply to Jonathan Wakely from comment #7) > Created attachment 39809 [details] > Use default member initializers. You attached the wrong patch?
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 --- Comment #7 from Jonathan Wakely --- Created attachment 39809 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39809=edit Use default member initializers. (In reply to Jonathan Wakely from comment #1) > Similar problem to PR 49894 but I don't think the fix is usable by libitm as > it depends on a C++11 language feature. Now that libitm is built with -std=gnu++14 default member initializers can be used, which uses the PTHREAD_xxx_INITIALIZER macros in a context where they are syntactically valid.
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 --- Comment #6 from Jonathan Wakely --- See https://gcc.gnu.org/bugs/
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 --- Comment #5 from Klaus Rudolph --- Hi Andrew, > Andrew Pinski changed: > >What|Removed |Added > > Status|NEW |WAITING > > --- Comment #4 from Andrew Pinski --- > How does this work for everyone else? Can you attach the preprocessed source? What exactly do you want to have? Complete build path after configure? Sorry for my stupid question! Regards Klaus
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 Andrew Pinski changed: What|Removed |Added Status|NEW |WAITING --- Comment #4 from Andrew Pinski --- How does this work for everyone else? Can you attach the preprocessed source?
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 Klaus Rudolph changed: What|Removed |Added Known to fail||4.9.2, 6.1.0 --- Comment #3 from Klaus Rudolph --- Still did *NOT* work for gcc 6.1.0
[Bug libitm/63907] libitm/config/posix/rwlock.cc doesn't compile
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63907 Andrew Pinski changed: What|Removed |Added Keywords||build Component|c++ |libitm --- Comment #2 from Andrew Pinski --- Does this work now?
