# [PATCH] Fix the exit code of MSVC build scripts on cygwin 4 messages from 2009-10-08 to 2009-10-09. Participants: Ramsay Jones, Alex Riesen, Junio C Hamano. Thread: https://gitlist.dev/t/21158 ## Ramsay Jones, 2009-10-08 15:33 Subject: [PATCH] Fix the exit code of MSVC build scripts on cygwin Message-ID: <4ACE064B.5020909@ramsay1.demon.co.uk> URL: https://gitlist.dev/e/4ACE064B.5020909%40ramsay1.demon.co.uk ``` During an MSVC build on cygwin, the make program did not notice when the compiler or linker exited with an error. This was caused by the scripts exiting with the value returned by system() directly. On POSIX-like systems, such as cygwin, the return value of system() has the exit code of the executed command encoded in the first byte (ie the value is shifted up by 8 bits). This allows the bottom 7 bits to contain the signal number of a terminated process, while the eighth bit indicates whether a core-dump was produced. (A value of -1 indicates that the command failed to execute.) The make program, however, expects the exit code to be encoded in the bottom byte. Futhermore, it apparently masks off and ignores anything in the upper bytes. However, these scripts are (naturally) intended to be used on the windows platform, where we can not assume POSIX-like semantics from a perl implementation (eg ActiveState). So, in general, we can not assume that shifting the return value right by eight will get us the exit code. In order to improve portability, we assume that a zero return from system() indicates success, whereas anything else indicates failure. Since we don't need to know the exact exit code from the compiler or linker, we simply exit with 0 (success) or 1 (failure). Signed-off-by: Ramsay Jones --- Hi *, I have tried to be conservative with this patch and, although I can confirm that it works great on cygwin, it should probably be tested (and Acked) by someone with an MSYS/Mingw installation. (or whatever Marius has installed :) ATB, Ramsay Jones compat/vcbuild/scripts/clink.pl | 4 +++- compat/vcbuild/scripts/lib.pl | 4 +++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/compat/vcbuild/scripts/clink.pl b/compat/vcbuild/scripts/clink.pl index 0ffd59f..26aec61 100644 --- a/compat/vcbuild/scripts/clink.pl +++ b/compat/vcbuild/scripts/clink.pl @@ -45,4 +45,6 @@ if ($is_linking) { push(@args, @cflags); } #printf("**** @args\n"); -exit system(@args); +system(@args) == 0 + or exit 1; +exit 0; diff --git a/compat/vcbuild/scripts/lib.pl b/compat/vcbuild/scripts/lib.pl index 68f6644..c11016d 100644 --- a/compat/vcbuild/scripts/lib.pl +++ b/compat/vcbuild/scripts/lib.pl @@ -23,4 +23,6 @@ while (@ARGV) { } unshift(@args, "lib.exe"); # printf("**** @args\n"); -exit system(@args); +system(@args) == 0 + or exit 1; +exit 0; -- 1.6.4 ``` ## Alex Riesen, 2009-10-08 20:13 Subject: Re: [PATCH] Fix the exit code of MSVC build scripts on cygwin Message-ID: <81b0412b0910081313x31f72916p6fddd1a23df154df@mail.gmail.com> URL: https://gitlist.dev/e/81b0412b0910081313x31f72916p6fddd1a23df154df%40mail.gmail.com In-Reply-To: <4ACE064B.5020909@ramsay1.demon.co.uk> ``` On Thu, Oct 8, 2009 at 17:33, Ramsay Jones wrote: > diff --git a/compat/vcbuild/scripts/clink.pl b/compat/vcbuild/scripts/clink.pl > index 0ffd59f..26aec61 100644 > --- a/compat/vcbuild/scripts/clink.pl > +++ b/compat/vcbuild/scripts/clink.pl > @@ -45,4 +45,6 @@ if ($is_linking) { >        push(@args, @cflags); >  } >  #printf("**** @args\n"); > -exit system(@args); > +system(@args) == 0 > +       or exit 1; > +exit 0; exit(system(@args) != 0); Yours looks a little verbose... ``` ## Junio C Hamano, 2009-10-09 06:49 Subject: Re: [PATCH] Fix the exit code of MSVC build scripts on cygwin Message-ID: <7vy6nl5ag0.fsf@alter.siamese.dyndns.org> URL: https://gitlist.dev/e/7vy6nl5ag0.fsf%40alter.siamese.dyndns.org In-Reply-To: <81b0412b0910081313x31f72916p6fddd1a23df154df@mail.gmail.com> ``` Alex Riesen writes: > On Thu, Oct 8, 2009 at 17:33, Ramsay Jones wrote: >> diff --git a/compat/vcbuild/scripts/clink.pl b/compat/vcbuild/scripts/clink.pl >> index 0ffd59f..26aec61 100644 >> --- a/compat/vcbuild/scripts/clink.pl >> +++ b/compat/vcbuild/scripts/clink.pl >> @@ -45,4 +45,6 @@ if ($is_linking) { >> push(@args, @cflags); >> } >> #printf("**** @args\n"); >> -exit system(@args); >> +system(@args) == 0 >> + or exit 1; >> +exit 0; > > exit(system(@args) != 0); > > Yours looks a little verbose... Thanks, will queue with a fixup. ``` ## Ramsay Jones, 2009-10-09 22:04 Subject: Re: [PATCH] Fix the exit code of MSVC build scripts on cygwin Message-ID: <4ACFB37B.8010602@ramsay1.demon.co.uk> URL: https://gitlist.dev/e/4ACFB37B.8010602%40ramsay1.demon.co.uk In-Reply-To: <7vy6nl5ag0.fsf@alter.siamese.dyndns.org> ``` Junio C Hamano wrote: > Alex Riesen writes: >>> -exit system(@args); >>> +system(@args) == 0 >>> + or exit 1; >>> +exit 0; >> exit(system(@args) != 0); >> >> Yours looks a little verbose... > > Thanks, will queue with a fixup. > Thanks! (Alex and Junio) I had this as my penultimate version, so I'm happy. [I changed it to be more explicit about the actual exit values returned by the script. (and thus more verbose :) ] ATB, Ramsay Jones ```