[PATCH] analyzer: fix for ICE in sm-fd.cc [PR106551]

[Immad Mir via Gcc-patches]

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 <mirim...@outlook.com>
---
 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();
+    }
+}
 
-- 
2.25.1