Michael Park created MESOS-3246:
-----------------------------------
Summary: Replace C-style variadic arguments with C++11 variadic
templates.
Key: MESOS-3246
URL: https://issues.apache.org/jira/browse/MESOS-3246
Project: Mesos
Issue Type: Task
Reporter: Michael Park
With the introduction of variadic templates, it's possible to write type-safe
n-ary functions. Aside from the lack of type-safety, varargs also come with
subtle pitfalls. For example, as pointed out in
[r25735|https://reviews.apache.org/r/25735/],
{quote}
N3797: 18.10 Other runtime support \[support.runtime\]
The restrictions that ISO C places on the second parameter to the va_start()
macro in header <stdarg.h>
are different in this International Standard. The parameter parmN is the
identifier of the rightmost parameter
in the variable parameter list of the function definition (the one just before
the ...). *If the parameter parmN is of a reference type,* or of a type that is
not compatible with the type that results when passing an argument for which
there is no parameter, *the behavior is undefined.*
{quote}
Currently, the following files have instances of varargs.
{noformat}
3rdparty/libprocess/3rdparty/stout/include/stout/format.hpp
3rdparty/libprocess/3rdparty/stout/include/stout/windows/format.hpp
3rdparty/libprocess/3rdparty/stout/include/stout/os/posix/shell.hpp
3rdparty/libprocess/3rdparty/stout/include/stout/os/windows/shell.hpp
src/jvm/jvm.hpp
src/jvm/jvm.cpp
{noformat}
For {{format.hpp}}, we can simply use {{asprintf}} rather than {{vasprintf}}.
An additional task here is to add {{asprintf}} in {{windows/format.hpp}}, but
this can simply delegate to {{vasprintf}} which is already implemented.
The transformation for {{shell.hpp}} is trivial since all it only depends on
{{format.hpp}}.
The JVM parts are likely to be the biggest undertaking, this needs further
investigation.
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