[lldb] Don't use NamedTemporaryFile to test compiler support

[JDevlieghere]

You cannot use a NamedTempFile with an external process because it may not be flushed to disk. The safest and most portable approach is to close the file, call the other process and then unlink the file manually.

Presumably this works fine on Linux, but it fails on Darwin when targeting remote-linux.

See https://bugs.python.org/issue29573

[llvmbot]

@llvm/pr-subscribers-lldb

Author: Jonas Devlieghere (JDevlieghere)

Changes

You cannot use a NamedTempFile with an external process because it may not be flushed to disk. The safest and most portable approach is to close the file, call the other process and then unlink the file manually.

Presumably this works fine on Linux, but it fails on Darwin when targeting remote-linux.

See https://bugs.python.org/issue29573

---

Full diff: https://github.com/llvm/llvm-project/pull/151387.diff

1 Files Affected:

• (modified) lldb/packages/Python/lldbsuite/test/dotest.py (+19-4)

diff --git a/lldb/packages/Python/lldbsuite/test/dotest.py b/lldb/packages/Python/lldbsuite/test/dotest.py
index 24236e779e51d..20eb3154b5775 100644
--- a/lldb/packages/Python/lldbsuite/test/dotest.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest.py
@@ -45,6 +45,21 @@
 from ..support import seven
 
 
+class OnDiskTempFile:
+    def __init__(self):
+        self.path = None
+
+    def __enter__(self):
+        fd, path = tempfile.mkstemp()
+        os.close(fd)
+        self.path = path
+        return self
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        if os.path.exists(self.path):
+            os.remove(self.path)
+
+
 def is_exe(fpath):
     """Returns true if fpath is an executable."""
     if fpath is None:
@@ -780,8 +795,8 @@ def canRunLibcxxTests():
         return True, "libc++ always present"
 
     if platform == "linux":
-        with tempfile.NamedTemporaryFile() as f:
-            cmd = [configuration.compiler, "-xc++", "-stdlib=libc++", "-o", f.name, "-"]
+        with OnDiskTempFile() as f:
+            cmd = [configuration.compiler, "-xc++", "-stdlib=libc++", "-o", f.path, "-"]
             p = subprocess.Popen(
                 cmd,
                 stdin=subprocess.PIPE,
@@ -840,8 +855,8 @@ def canRunMsvcStlTests():
     if platform != "windows":
         return False, f"Don't know how to build with MSVC's STL on {platform}"
 
-    with tempfile.NamedTemporaryFile() as f:
-        cmd = [configuration.compiler, "-xc++", "-o", f.name, "-E", "-"]
+    with OnDiskTempFile() as f:
+        cmd = [configuration.compiler, "-xc++", "-o", f.path, "-E", "-"]
         p = subprocess.Popen(
             cmd,
             stdin=subprocess.PIPE,

[bulbazord]

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