This is likely only the tip of the ice berg, but this particular bug
caused any double-free on a glibc system to turn into a deadlock! It is
not generally safe to either allocate or release heap memory from within
the signal handler. The 'pop_back()' in RemoveFilesToRemove was deleting
memory and causing the deadlock. What's worse, eraseFromDisk in PathV1
has lots of allocation and deallocation paths. We even passed 'true' in
a place that would have caused the *signal handler* to try to run the
'system' system call and shell out to 'rm -rf'. That was never going to
work...
This patch switches the file removal to use a vector of strings so that
the exact text needed for the 'unlink' system call can be stored there.
It switches the loop to be a boring indexed loop, and directly calls
unlink without looking at the error. It also works quite hard to ensure
that calling 'c_str()' is safe, by ensuring that the non-signal-handling
code path that manipulates the vector always leaves it in a state where
every element has already had 'c_str()' called at least once.
I dunno exactly how overkill this is, but it fixes the
deadlock-on-double free issue, and seems likely to prevent any other
issues from sneaking up.
Sorry for not having a test case, but I *really* don't know how to test
signal handling code easily....
llvm-svn: 158580
Apart from being slightly cheaper, this fixes a real bug that hits 32 bit
linux systems. When passing a file larger than 2G to be linked (which isn't
that uncommon with large projects such as WebKit), clang's driver checks
if the file exists but the file size doesn't fit in an off_t and stat(2)
fails with EOVERFLOW. Clang then says that the file doesn't exist instead
of passing it to the linker.
llvm-svn: 157891
- Just use sys::Process::GetRandomNumber instead of having two poor
implementations.
- This is ~70 times (!) faster on my OS X machine.
llvm-svn: 156238
When building LLVM on Linux with libc++ with CMake TIME_WITH_SYS_TIME is
undefined, and HAVE_SYS_TIME_H is defined. This ends up including
sys/time.h but not time.h. Unix/TimeValue.inc requires time.h for asctime_r
and localtime. libstdc++ seems to include time.h anyway, but libc++ does
not.
Fix this by always including time.h
llvm-svn: 155382
The problem is that the struct file_status on UNIX systems has two
members called st_dev and st_ino; those are also members of the
struct stat, and they are reserved identifiers which can also be
provided as #define (and this is the case for st_dev on Hurd).
The solution (attached) is to rename them, for example adding a
"fs_" prefix (= file status) to them.
Patch by Pino Toscano
llvm-svn: 155354
Unify default construction of error_code uses on this idiom so that users don't
feel compelled to make static globals for naming convenience. (unfortunately I
couldn't make the original ctor private as some APIs don't return their result,
instead using an out parameter (that makes sense to default construct) - which
is a bit of a pity. I did, however, find/fix some cases of unnecessary default
construction of error_code before I hit the unfixable cases)
llvm-svn: 150197
or Clang is using this, and it would be hard to use it correctly given
the thread hostility of the function. Also, it never checked the return
which is rather dangerous with chdir. If someone was in fact using this,
please let me know, as well as what the usecase actually is so that
I can add it back and make it more correct and secure to use. (That
said, it's never going to be "safe" per-se, but we could at least
document the risks...)
llvm-svn: 148211
Get back getHostTriple.
For JIT compilation, use the host triple instead of the default
target: this fixes some JIT testcases that used to fail when the
compiler has been configured as a cross compiler.
llvm-svn: 147542
This was only needed to locate llvm-gcc's installation directory when clang
falls back to run llvm-gcc for i386 kexts. As of clang svn r140187, we're
now just searching paths with several different Darwin versions on either
side of the current version, so this is no longer needed.
llvm-svn: 140188
When this variable is set, "uname -r" will return its value instead of the
real OS version. Make this affect LLVM's triple for consistency.
<rdar://problem/9919167>
llvm-svn: 137111
screwy things by setting PWD != getcwd(). For example, some developers I know
will use this to control the value in gcc's DW_AT_comp_dir value in debug
output. With this patch, that trick will now work on clang too.
The only other effect of this change is that the static analysis will now
respect $PWD when reporting the directory of the files in its HTML output. I
think that's fine.
llvm-svn: 136459
If true and 'model' parameter is not an absolute path, a temp directory will be prepended.
Make it true by default to match current behaviour.
llvm-svn: 136310
This change allows bugpoint to pinpoint the "opt" pass and bitcode
segment responsible for a crash caused by miscompilation. At least it
works well for me now, without having to create any custom execution
wrappers.
llvm-svn: 131186
Eric Christopher