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Some of these are terrific changes! E.g., OpenMP 4.0 and Cilk Plus support, wew! I also love that ``gcc`` now defaults to ``-std=gnu11`` instead of ``-std=gnu89

Some of these are terrific changes! E.g., OpenMP 4.0 and Cilk Plus support, wew! I also love that ``gcc`` now defaults to ``-std=gnu11`` instead of ``-std=gnu89``; what a huge step forward! But, there were a couple of things in here that I was hoping to see but did not find (namely, it seems gcc still does not have ``-Weverything``). While I am glad to see gcc making progress, I feel bound to clang until gcc's warning/error reporting can get up-to-speed.

reidrac 11y ago
Apparently -Wall and -Wextra is believed to be enough; not sure what to expect with -Weverything but I'm intrigued :) EDIT: interesting indeed. Thanks for the pointer! (Add warning levels) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53313 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53313
- mkaufmann 11y ago
  I like to use -Wpedantic for my own projects to keep the code clean and it helped my well. Its not included in -Wall and -Wextra.
- halosghost 11y ago
  Yeah, as has been mentioned many times before `-Wall -Wextra` leaves out a ton of warnings/errors (despite what the names imply). `-Weverything` is an alias for enabling all warnings. I find it much better practice to enable all warnings and then selectively disable the ones which warn me about things I have done intentionally through pragmas in the code.
thoughtpolice 11y ago
GCC 5.1 defaults to having color diagnostics set to `auto`, meaning it will display nice, beautiful diagnostics like Clang does on your terminal, if that's what you're referring to. (You can also get these with GCC 4.9, too, using the `GCC_COLORS` environment variable). Personally I don't care about that as much as the optimization improvements this time arond, it seems. Better devirtualization? AutoFDO? Reuse of the PIC hard register, especially? (That will be a great win on 32 bit machines, and makes it all the more possible to enable things like PIE for 32-bit applications, where it would otherwise be a big penalty, as well as many other things.)
- halosghost 11y ago
  Haha, I wasn't actually referring to colored warning/error output (though it is a nice plus!). I was mostly referring to `clang`'s `-Weverything` and the absence of any such alias for `gcc`.
thoughtpolice 11y ago
GCC 5.1 defaults to having color diagnostics set to `auto`, meaning it will display nice, beautiful diagnostics like Clang does on your terminal, if that's what you're referring to.
BinaryIdiot 11y ago
> namely, it seems gcc still does not have ``-Weverything`` I would love to have a -Weverything; as a fairly rusty C++ dev I originally thought -Wall was supposed to have, you know, all but was pretty surprised to learn it didn't actually contain all. It would be great if they deprecated -Wall and made it so -Weverything always did all warnings (including any newly introduced warnings).
- jeorgun 11y ago
  Clang's -Weverything isn't really as useful as it sounds; since it includes fairly-to-completely useless warnings like -Wc++98-compat, -Wpadded, or -Wweak-vtables, you'll end up spending so much time playing warning whack-a-mole that you might as well have not enabled the thing in the first place. At least that's been my experience.
  - halosghost 11y ago
    I completely disagree. It's true that some of the warnings it enables aren't terribly useful, but being able to enable all warnings is very helpful instead of having to manually list ~40 flags. Additionally, -Wpadded and the like are actually helpful for optimizations. Plus, writing code (in C, I cannot speak for Cxx) which results in no warning output from `-Weverything` is actually not that difficult to do, and generally the result is that you've written more robust code in the process. A lot of projects are now trying to move to compile with `-Weverything` and not disable any warnings, and I personally think it's a great move.
    - jeorgun 11y ago
      For C, I'd agree that it's useful. The flags I listed have issues specifically for C++. -Wc++98-compat, on a C++11 or C++14 project, is about as helpful as you'd expect. -Wpadded is triggered pretty reliably by subclassess. And so forth. Of course it is possible to specifically disable useless warnings, but in my experience it's just as easy to add a reasonable selection of flags (say, -Wall -Wextra -Wold-style-cast -Wconversion -Wsign-conversion) than to start with -Weverything and work backwards. Still, it has been some time since I've tried using it; maybe I ought to give it another chance.
nn3 11y ago
gcc $(gcc -v --help 2>&1 | awk '/-W/ && !/=/ && !/[oO]ptions/ && !/larger-than/ { print $1 }') Not particularly useful though.

reidrac 11y ago

Apparently -Wall and -Wextra is believed to be enough; not sure what to expect with -Weverything but I'm intrigued :) EDIT: interesting indeed. Thanks for the pointer! (Add warning levels) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53313 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53313

mkaufmann 11y ago
I like to use -Wpedantic for my own projects to keep the code clean and it helped my well. Its not included in -Wall and -Wextra.
halosghost 11y ago
Yeah, as has been mentioned many times before `-Wall -Wextra` leaves out a ton of warnings/errors (despite what the names imply). `-Weverything` is an alias for enabling all warnings. I find it much better practice to enable all warnings and then selectively disable the ones which warn me about things I have done intentionally through pragmas in the code.

thoughtpolice 11y ago

GCC 5.1 defaults to having color diagnostics set to `auto`, meaning it will display nice, beautiful diagnostics like Clang does on your terminal, if that's what you're referring to. (You can also get these with GCC 4.9, too, using the `GCC_COLORS` environment variable). Personally I don't care about that as much as the optimization improvements this time arond, it seems. Better devirtualization? AutoFDO? Reuse of the PIC hard register, especially? (That will be a great win on 32 bit machines, and makes it all the more possible to enable things like PIE for 32-bit applications, where it would otherwise be a big penalty, as well as many other things.)

halosghost 11y ago
Haha, I wasn't actually referring to colored warning/error output (though it is a nice plus!). I was mostly referring to `clang`'s `-Weverything` and the absence of any such alias for `gcc`.

thoughtpolice 11y ago

GCC 5.1 defaults to having color diagnostics set to `auto`, meaning it will display nice, beautiful diagnostics like Clang does on your terminal, if that's what you're referring to.

BinaryIdiot 11y ago

> namely, it seems gcc still does not have ``-Weverything`` I would love to have a -Weverything; as a fairly rusty C++ dev I originally thought -Wall was supposed to have, you know, all but was pretty surprised to learn it didn't actually contain all. It would be great if they deprecated -Wall and made it so -Weverything always did all warnings (including any newly introduced warnings).

jeorgun 11y ago
Clang's -Weverything isn't really as useful as it sounds; since it includes fairly-to-completely useless warnings like -Wc++98-compat, -Wpadded, or -Wweak-vtables, you'll end up spending so much time playing warning whack-a-mole that you might as well have not enabled the thing in the first place. At least that's been my experience.
- halosghost 11y ago
  I completely disagree. It's true that some of the warnings it enables aren't terribly useful, but being able to enable all warnings is very helpful instead of having to manually list ~40 flags. Additionally, -Wpadded and the like are actually helpful for optimizations. Plus, writing code (in C, I cannot speak for Cxx) which results in no warning output from `-Weverything` is actually not that difficult to do, and generally the result is that you've written more robust code in the process. A lot of projects are now trying to move to compile with `-Weverything` and not disable any warnings, and I personally think it's a great move.
  - jeorgun 11y ago
    For C, I'd agree that it's useful. The flags I listed have issues specifically for C++. -Wc++98-compat, on a C++11 or C++14 project, is about as helpful as you'd expect. -Wpadded is triggered pretty reliably by subclassess. And so forth. Of course it is possible to specifically disable useless warnings, but in my experience it's just as easy to add a reasonable selection of flags (say, -Wall -Wextra -Wold-style-cast -Wconversion -Wsign-conversion) than to start with -Weverything and work backwards. Still, it has been some time since I've tried using it; maybe I ought to give it another chance.

nn3 11y ago

gcc $(gcc -v --help 2>&1 | awk '/-W/ && !/=/ && !/[oO]ptions/ && !/larger-than/ { print $1 }') Not particularly useful though.