bug #54495 [Process] Don't call sigprocmask if there is no ignored si…

…gnals (joelwurtz)

This PR was merged into the 7.1 branch.

Discussion
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[Process] Don't call sigprocmask if there is no ignored signals

| Q             | A
| ------------- | ---
| Branch?       | 7.1
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        |
| License       | MIT

It seems that passing an empty signal list makes an error on php 8.4 see https://github.com/symfony/symfony/actions/runs/8566954369/job/23477741854

This should fix this case

Commits
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3cf4e36 fix(process): don't call sigprocmask if there is no ignored signals

src/Symfony/Component/Process/Process.php

@@ -350,7 +350,7 @@ public function start(?callable $callback = null, array $env = []): void
 
         $oldMask = [];
 
-        if (\function_exists('pcntl_sigprocmask')) {
+        if ($this->ignoredSignals && \function_exists('pcntl_sigprocmask')) {
             // we block signals we want to ignore, as proc_open will use fork / posix_spawn which will copy the signal mask this allow to block
             // signals in the child process
             pcntl_sigprocmask(\SIG_BLOCK, $this->ignoredSignals, $oldMask);
@@ -359,7 +359,7 @@ public function start(?callable $callback = null, array $env = []): void
         try {
             $process = @proc_open($commandline, $descriptors, $this->processPipes->pipes, $this->cwd, $envPairs, $this->options);
         } finally {
-            if (\function_exists('pcntl_sigprocmask')) {
+            if ($this->ignoredSignals && \function_exists('pcntl_sigprocmask')) {
                 // we restore the signal mask here to avoid any side effects
                 pcntl_sigprocmask(\SIG_SETMASK, $oldMask);
             }