Currently the top-level driver handles SIGINT by immediately killing
itself even when the driver has subprocesses (e.g. cc1, as) running. I
don't think this is a good idea because
1. if the top-level driver is waiting on a hanging subprocess,
pressing ^C will kill the driver but it may not necessarily kill the
subprocess; an unresponsive, perhaps busy-looping subprocess may be
running in the background yet the compiler will seem to have to
terminated successfully.
2. when debugging gcc with "gcc -wrapper gdb,--args" we are unable to
use ^C from within the GDB subprocess because pressing ^C immediately
kills the driver and we lose our terminal. This makes debugging more
inconvenient.
This patch fixes these two issues by having the driver ignore SIGINT
while a subprocess is running. The driver instead will have to wait for
the subprocess to exit before it terminates, like usual.
I tested this change by running "gcc -wrapper gdb", "gcc -wrapper
valgrind" and plain old "gcc" in various ways (-pipe, -flto, -c, etc)
and pressing ^C during compilation. I noticed no differences in
behavior or promptness other than finally being able to use ^C inside
GDB.
Does this change look OK for trunk after a successful bootstrap +
regtest on x86_64-unknown-linux-gnu?
---
gcc/gcc.c | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/gcc/gcc.c b/gcc/gcc.c
index 653ca8d..0802f41 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -2653,7 +2653,11 @@ add_sysrooted_prefix (struct path_prefix *pprefix, const
char *prefix,
add_prefix (pprefix, prefix, component, priority,
require_machine_suffix, os_multilib);
}
-
+
+/* True if the SIGINT signal should be ignored by the driver's
+ signal handler. */
+static bool ignore_sigint_p;
+
/* Execute the command specified by the arguments on the current line of spec.
When using pipes, this includes several piped-together commands
with `|' between them.
@@ -2839,6 +2843,10 @@ execute (void)
if (pex == NULL)
fatal_error ("pex_init failed: %m");
+ /* A SIGINT raised while subprocesses are running should not kill the
+ driver. */
+ ignore_sigint_p = true;
+
for (i = 0; i < n_commands; i++)
{
const char *errmsg;
@@ -2878,6 +2886,8 @@ execute (void)
if (!pex_get_status (pex, n_commands, statuses))
fatal_error ("failed to get exit status: %m");
+ ignore_sigint_p = false;
+
if (report_times || report_times_to_file)
{
times = (struct pex_time *) alloca (n_commands * sizeof (struct
pex_time));
@@ -2893,6 +2903,9 @@ execute (void)
if (WIFSIGNALED (status))
{
+ if (WTERMSIG (status) == SIGINT)
+ raise (SIGINT);
+ else
#ifdef SIGPIPE
/* SIGPIPE is a special case. It happens in -pipe mode
when the compiler dies before the preprocessor is done,
@@ -6710,6 +6723,12 @@ set_input (const char *filename)
static void
fatal_signal (int signum)
{
+ if (signum == SIGINT && ignore_sigint_p)
+ {
+ signal (signum, fatal_signal);
+ return;
+ }
+
signal (signum, SIG_DFL);
delete_failure_queue ();
delete_temp_files ();
--
2.2.0.rc1.23.gf570943
