Improve pdump file search and 'pdumper-stats'

* src/pdumper.c (pdumper_record_wd): New function.
(pdumper_load): Use xstrdup instead of strdup, as on
MS-Windows the latter uses the wrong heap.  Don't free a
NULL pointer.
* src/emacs.c (load_pdump): Support the use case where the
Emacs binary was renamed: look in exec-directory for the
pdump file whose base name is derived from the Emacs binary,
in addition to just emacs.pdmp.
(main): Call pdumper_record_wd to prepend CWD to the pdump
file name.
* src/fileio.c (file_name_absolute_p): Now extern.
* src/lisp.h (file_name_absolute_p): Add prototype.
* src/pdumper.h (pdumper_record_wd): Add prototype.

* doc/emacs/cmdargs.texi (Initial Options): Update the
documentation of where Emacs looks for the dump file.

1 files changed, 10 insertions, 6 deletions

diff --git a/doc/emacs/cmdargs.texi b/doc/emacs/cmdargs.texi
index b49126764a6..00d5be70eb2 100644
--- a/doc/emacs/cmdargs.texi
+++ b/doc/emacs/cmdargs.texi
@@ -387,12 +387,16 @@ elisp, The GNU Emacs Lisp Reference Manual}.
 @item --dump-file=@var{file}
 @opindex --dump-file
 @cindex specify dump file
-Load the dumped Emacs state from the named @var{file}.  By default,
-Emacs will look for its dump state in a file named
-@file{@var{emacs}.pdmp} in the directory of the executable, where
-@var{emacs} is the name of the Emacs executable file, normally just
-@file{emacs}.  However, if you rename or move the dump file to a
-different place, you can use this option to tell Emacs where to find
+Load the dumped Emacs state from the named @var{file}.  By default, an
+installed Emacs will look for its dump state in a file named
+@file{@var{emacs}.pdmp} in the directory where the Emacs installation
+puts the architecture-dependent files; the variable
+@code{exec-directory} holds the name of that directory.  @var{emacs}
+is the name of the Emacs executable file, normally just @file{emacs}.
+(When you invoke Emacs from the @file{src} directory where it was
+built without installing it, it will look for the dump file in the
+directory of the executable.)  If you rename or move the dump file to
+a different place, you can use this option to tell Emacs where to find
 that file.
 @end table