fweimer

18 ms·

451.
by fweimer 2y ago
GCC does the same thing to this day. As a result, the GCC AST hasn't much S in it, except for some OpenMP constructs (which are preserved in the AST). It's not great if you want to write syntax-driven tools.
452.
by fweimer 2y ago
Is this save once more because it moved back to Cloudflare? ;; QUESTION SECTION: ;cdn.polyfill.io. IN A ;; ANSWER SECTION: cdn.polyfill.io. 553 IN CNAME cdn.polyfill.io.cdn.cloudflare.net. cdn.polyfill.io.cdn.clo
453.
by fweimer 2y ago
I've used it to confirm that a service computes the RSA signature correctly and just advertises the wrong public key. If the signature is always consistent with some public key, but it's not the right one, that's not very int
454.
by fweimer 2y ago
It does not prevent all writes, it only prevents protection flag changes, mapping over the region, and unmapping. As far as I understand it, sealed memory might even be writable. If the sealed memory is read-only, debuggers and other tools
455.
by fweimer 2y ago
Java IDEs have had optional reformat on safe for a long time. https://help.eclipse.org/latest/index.jsp?topic=%2Forg.eclip...
456.
by fweimer 2y ago
I think the challenge here is that it only happens for a type error, not a successful compilation. Each time this happens, the programmer would try to fix the type error, usually invalidating the cache. I'm not so sure the problem is i
457.
by fweimer 2y ago
Try this: let f0 = fun x -> (x, x) in let f1 = fun y -> f0(f0 y) in let f2 = fun y -> f1(f1 y) in let f3 = fun y -> f2(f2 y) in let f4 = fun y -> f3(f3 y) in let f5 = fun y
458.
by fweimer 2y ago
I know that historically, we were taught that NP-complete problems are unsolvable for interesting problem sizes, but that was already a bit of lie in when I went to university. (TSP was presented as a warning example, but even back then, ve
459.
by fweimer 2y ago
Well, GCC supports -fimplicit-constexpr these days: https://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Dialect-Optio...
460.
by fweimer 2y ago
Example: You are editing a table row with some application, but when you try to save the changes, the system discovered that the row has been deleted from the table. The business logic does not permit you to create rows arbitrarily, so a ne
461.
by fweimer 2y ago
That's 750$/month now, I think: https://elements.heroku.com/addons/heroku-postgresql#pricing (Standard 4)
462.
by fweimer 2y ago
Glad to be of help. Note that it's actually GLIBC_TUNABLES=glibc.cpu.hwcaps=SHSTK to enable it with Fedora 40 glibc (and the program needs to be built with -fcf-protection).
463.
by fweimer 2y ago
You can get the shadow stack pointer using the RDSSPQ instruction. The kernel documentation shows how the shadow stack size is obtained for the main thread. Threads created explicitly using clone3 have the specified shadow stack size. I thi
464.
by fweimer 2y ago
Fedora 40 and later have shadow stack support in userspace. It's currently opt-in with glibc (`export GLIBC_TUNABLES=glibc.cpu.x86_shstk=on` is one way to switch it on I believe). The plan is to make this self-tuning eventually in glib
465.
by fweimer 2y ago
These kinds of warnings need optimizations enabled. $ gcc -O2 -Wall -c t.c t.c: In function ‘main’: t.c:3:14: warning: array subscript 20 is outside array bounds of ‘int[10]’ [-Warray-bounds] 3 | return *(x+20);
466.
by fweimer 2y ago
How so? You can just assume that some conjecture is true and proceed with your work. (For some conjectures that is acceptable, for others, not so much.) An interesting proof would have to show something more than just the truth: maybe it&#x
467.
by fweimer 2y ago
If you ship the library, the requirements for the library itself are very similar to the GPL. The difference you describe mostly applies to system libraries (those libraries that are not distributed alongside applications).
468.
by fweimer 2y ago
Are there any good heuristics for adding trampolines if the underlying architecture does not support tail calls? (With the closed-world assumption.) Maybe breadth-first search on the callgraph, inserting trampolines at the first circle? And
469.
by fweimer 2y ago
The numbers here https://netsplit.de/networks/top100.php are much lower than what I remember from twenty years ago, and the Internet Archive seems to support this: https://web.archive.org/web/20060
470.
by fweimer 2y ago
You can write a compiler plugin that rejects constructs you don't like. Even GCC doesn't immediately lower the more complex (more controversial) C++ constructs. There's an existing system headers mechanism, so it's proba
471.
by fweimer 2y ago
You don't have to update, it's just that developers seem to like to run the latest stuff, and many appear to build production binaries on their laptops (rather than in a controlled build environment, where dependencies are tightly
472.
by fweimer 2y ago
Recent libstdc++ has a _dl_find_object@GLIBC_2.35 dependency, so it's not exactly trivial anymore to link a C++ program against a older, side-installed glibc version because it won't have that symbol. It's possible to work ar
473.
by fweimer 2y ago
Only the dynamically linked bits, the statically linked startup code and libc_nonshared.a are missing from newer versions. Most programs don't need them (who needs working ELF constructors in the main program?). The libc_nonshared.a bi
474.
by fweimer 2y ago
I used to think that binary compatibility benefits proprietary applications, but I'm not so sure anymore. From a commercial perspective, when we break binary compatibility (not that we want to), it's an opportunity for selling mor
475.
by fweimer 2y ago
Isn't it ”We are the dot in oracle.com” nowadays?
476.
by fweimer 2y ago
I know people use it because Apple Mail generates out-of-office responses to mailing list mail (with List-Id: headers and other indicators).
477.
by fweimer 2y ago
It makes more sense now that Intel and AMD retconned naturally-aligned 128-bit atomic loads into the ISA: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104688 (AMD's confirmation is in comment 10.)
478.
by fweimer 2y ago
There is a socket option, SO_SNDLOWAT. It's not implement Linux according to the manual page. The description in UNIX Network Programming and TCP Illustrated conflict, too. So it's probably not useful.
479.
by fweimer 2y ago
The original German article makes it clear it's only about the web front end and some ancillary services, not the video streaming service as such. The latter seems to be mostly Akamai-based.
480.
by fweimer 2y ago
Is it really that advanced? Do you actually need more logic tools than what was used in the 19th century to formalize real analysis? Things get complicated if you want to put the proofs into the types, but I don't think this is the mai

More ›