[gcc r17-180] analyzer: add test_passthrough for getenv

[David Malcolm]

https://gcc.gnu.org/g:7367e7335bfefe9e881af302621e7d37fe00a4c0

commit r17-180-g7367e7335bfefe9e881af302621e7d37fe00a4c0
Author: Ridham Khurana <khurana.ridham222@gmail.com>
Date:   Sun Mar 22 01:07:40 2026 +0530

    analyzer: add test_passthrough for getenv
    
    Add a test_passthrough case for getenv to ensure the known_function
    correctly handles purely symbolic arguments.
    
    gcc/testsuite/ChangeLog:
            * gcc.dg/analyzer/getenv-1.c (test_passthrough): New test.
    
    Signed-off-by: Ridham Khurana <khurana.ridham222@gmail.com>

Diff:
---
 gcc/testsuite/gcc.dg/analyzer/getenv-1.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/gcc/testsuite/gcc.dg/analyzer/getenv-1.c b/gcc/testsuite/gcc.dg/analyzer/getenv-1.c
index 43afdf1f115c..61e87e8db3df 100644
--- a/gcc/testsuite/gcc.dg/analyzer/getenv-1.c
+++ b/gcc/testsuite/gcc.dg/analyzer/getenv-1.c
@@ -41,6 +41,11 @@ void test_getenv_returns_nonnull (void)
   __analyzer_eval (p != NULL); /* { dg-warning "TRUE" } */
 }
 
+char *test_passthrough (const char *name)
+{
+  return getenv (name);
+}
+
 void test_unterminated (void)
 {
   char buf[3] = "abc";