- Add special test to detect the case of -1 * INTMAX_MIN
- Protect against elimination of the test division by the optimizer
Garrett Cooper noticed that the overflow checks were incomplete, and Bruce
Evans suggested the use of the "volatile" qualifier to counter the effect
of the undefined behaviour, when the prior multiplication caused overflow,
and he also suggested improvements to the comments.
Reviewed by: bde
MFC after: 1 week
This compiler flag enforces that that people either mark variables
static or use an external declarations for the variable, similar to how
-Wmissing-prototypes works for functions.
Due to the fact that Yacc/Lex generate code that cannot trivially be
changed to not warn because of this (lots of yy* variables), add a
NO_WMISSING_VARIABLE_DECLARATIONS that can be used to turn off this
specific compiler warning.
Announced on: toolchain@
to re-establishment of 64bit arithmetic, but is committed separately, to
not obscure that conversion. This commit does not change the observed
behaviour of expr in any way. Style will be fixed in a follow-up commit.
again. This brings back the behaviour of expr in FreeBSD-4, which had been
reverted due to an assumed incompatbility with POSIX.1 for FreeBSD-5.
This issue has been discussed in the freebsd-standards list, and the
consensus was, that POSIX.1 is in fact not violated by this extension,
since it affects only cases of POSIX undefined behaviour (overflow of
signed long).
Other operating systems did upgrade their versions of expr to support
64bit range, after it had been initially brought to FreeBSD. They have
used it for a decade without problems, meanwhile.
The -e option is retained, but it will only select less strict checking
of numeric parameters (leading white-space, leading "+" are allowed and
skipped, an empty string is considered to represent 0 in numeric context.)
The call of check_utility_compat() as a means of establishing backwards
compatibility with FreeBSD-4 is considered obsolete, but preserved in
this commit. It is expected to be removed in a later revision of this
file.
Reviewed by: bde, das, jilles
MFC after: 2 month (those parts that do not violate POLA)
The three examples are better done using sh(1) itself these days.
The example
expr -- "$a" : ".*"
is incorrect in the general case, as "$a" may be an operator.
MFC after: 2 weeks
Revert to using the .Tn POSIX and .Tn ANSI instead of \*[Px] and \*[Ai]
strings; using these strings is unsafe in troff mode, as they include a
change in a font size.
Approved by: re
whether a named utility should behave in FreeBSD 4.x-compatible mode
or in a standard mode (default standard). The configuration is done
malloc(3)-style, with either an environment variable or a symlink.
Update expr(1) to use this new interface.
is required to be oblivious to overflow and to use the data type `long'.
(Division by zero is undefined in ISO C so it's still OK to check for it
here.) Add a new `-e' flag to get the old, more useful behavior.
- expr must conform to the Utility Syntax Guidelines, so use
getopt() to eat the (non-existent) options.
- Use the Standard type intmax_t for arithmetic.
- If an argument cannot be *completely* converted to an integer, then
it is a string.
Additionally make some style cleanups near the modified lines. This
utility is still not completely style-compliant.
o Old-style K&R declarations have been converted to new C89 style
o register has been removed
o prototype for main() has been removed (gcc3 makes it an error)
o int main(int argc, char *argv[]) is the preferred main definition.
o Attempt to not break style(9) conformance for declarations more than
they already are.
o gc some #ifdef sun ... #endif code
Approved by: arch@, new style(9)
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
