Jim Meyering wrote:
> +2008-10-16 Jim Meyering <[EMAIL PROTECTED]>
> +
> + openat-die.c: avoid 'no previous prototype' warning
> + * lib/openat-die.c: Include "openat.h".
> + Reported by Reuben Thomas <[EMAIL PROTECTED]>.
Thanks to this change, I now get a compilation error when compiling for mingw:
i386-pc-mingw32-gcc -DHAVE_CONFIG_H -I. -I.. -Wall -g -O2 -MT openat-die.o
-MD -MP -MF .deps/openat-die.Tpo -c -o openat-die.o openat-die.c
openat-die.c:33: error: conflicting types for 'openat_save_fail'
openat.h:97: error: previous declaration of 'openat_save_fail' was here
At first sight, the two declarations look the same:
void openat_save_fail (int)
modulo a 'noreturn` attribute of which we know that it is irrelevant for
function type purposes. The preprocessed output, however, reveals what's
happening:
void
openat_save_fail (int (*_errno()))
{
error (exit_failure, (*_errno()),
((const char *) ("unable to record current working directory")));
...
So the function declared in the header file as taking an 'int' parameter
is now defined with a function pointer parameter, and this function is
immediately invoked. This would have crashed at runtime, trying to transfer
control to a small address in the range 0 < _errno < 200.
Here's a proposed fix:
2008-10-18 Bruno Haible <[EMAIL PROTECTED]>
* lib/openat-die.c (openat_save_fail, openat_restore_fail): Rename
the parameter from 'errno' to 'errnum'. Fixes a compilation error on
mingw.
--- lib/openat-die.c.orig 2008-10-19 02:42:49.000000000 +0200
+++ lib/openat-die.c 2008-10-19 02:40:41.000000000 +0200
@@ -29,9 +29,9 @@
#define N_(msgid) msgid
void
-openat_save_fail (int errno)
+openat_save_fail (int errnum)
{
- error (exit_failure, errno,
+ error (exit_failure, errnum,
_("unable to record current working directory"));
/* The `noreturn' attribute cannot be applied to error, since it returns
@@ -42,9 +42,9 @@
}
void
-openat_restore_fail (int errno)
+openat_restore_fail (int errnum)
{
- error (exit_failure, errno,
+ error (exit_failure, errnum,
_("failed to return to initial working directory"));
/* As above. */
