On 2/10/24 10:26 AM, Andrew Burgess wrote:
GDB makes use of the libiberty function buildargv for splitting the
inferior (program being debugged) argument string in the case where
the inferior is not being started under a shell.
I have recently been working to improve this area of GDB, and have
tracked done some of the unexpected behaviour to the libiberty
function buildargv, and how it handles backslash escapes.
For reference, I've been mostly reading:
https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html
The issues that I would like to fix are:
1. Backslashes within single quotes should not be treated as an
escape, thus: '\a' should split to \a, retaining the backslash.
2. Backslashes within double quotes should only act as an escape if
they are immediately before one of the characters $ (dollar),
` (backtick), " (double quote), ` (backslash), or \n (newline). In
all other cases a backslash should not be treated as an escape
character. Thus: "\a" should split to \a, but "\$" should split to
$.
3. A backslash-newline sequence should be treated as a line
continuation, both the backslash and the newline should be removed.
I've updated libiberty and also added some tests. All the existing
libiberty tests continue to pass, but I'm not sure if there is more
testing that should be done, buildargv is used within lto-wraper.cc,
so maybe there's some testing folk can suggest that I run?
I'm not immediately aware of other tests that we should be running other
than the usual bootstrap & regression test.
You do need a ChangeLog entry or the pre-commit hooks are going to
complain loudly.
OK for the trunk with the usual testing. I know you're typically on the
GDB side of things, so if you need help on the testing GCC, let us know.
jeff
