[gcc r13-2051] analyzer: fix for ICE in sm-fd.cc [PR106551]

[Immad Mir <mir@gcc.gnu.org>]

https://gcc.gnu.org/g:ed7e7620188dc0e653815bdd40d8802bd5446638

commit r13-2051-ged7e7620188dc0e653815bdd40d8802bd5446638
Author: Immad Mir <mirimmad@outlook.com>
Date:   Mon Aug 15 22:21:27 2022 +0530

    analyzer: fix for ICE in sm-fd.cc [PR106551]
    
    This patch fixes the ICE caused by valid_to_unchecked_state
    in sm-fd.cc by exiting early if first argument of any "dup"
    functions is invalid.
    
    gcc/analyzer/ChangeLog:
            PR analyzer/106551
            * sm-fd.cc (check_for_dup): exit early if first
            argument is invalid for all dup functions.
    
    gcc/testsuite/ChangeLog:
            PR analyzer/106551
            * gcc.dg/analyzer/fd-dup-1.c: New testcase.
    
    Signed-off-by: Immad Mir <mirimmad@outlook.com>

Diff:
---
 gcc/analyzer/sm-fd.cc                    |  3 +--
 gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c | 11 +++++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/gcc/analyzer/sm-fd.cc b/gcc/analyzer/sm-fd.cc
index e02b86baad1..505d598f3f0 100644
--- a/gcc/analyzer/sm-fd.cc
+++ b/gcc/analyzer/sm-fd.cc
@@ -976,8 +976,7 @@ fd_state_machine::check_for_dup (sm_context *sm_ctxt, const supernode *node,
     {
       check_for_open_fd (sm_ctxt, node, stmt, call, callee_fndecl,
 			 DIRS_READ_WRITE);
-      if (kind == DUP_1)
-	return;
+      return;
     }
   switch (kind)
     {
diff --git a/gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c b/gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c
index b971d31b1c7..b4f43e7f0ef 100644
--- a/gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c
+++ b/gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c
@@ -245,4 +245,15 @@ test_22 (int flags)
     close (fd);
 }
 
+void do_something();
+void
+test_23 ()
+{
+    int nullfd = -1;
+    int fd = 1;
+    if (dup2 (nullfd, fd) < 0) /* { dg-warning "'dup2' on possibly invalid file descriptor 'nullfd'" } */
+    {
+        do_something();
+    }
+}