[3.13] GH-130673: Gracefully handle missing sections in JIT build (GH-131749)

(cherry picked from commit a26a301)
Co-authored-by: Bojun Ren <[email protected]>
Co-authored-by: Bénédikt Tran <[email protected]>

Author: 3 people

Misc/NEWS.d/next/Build/2025-03-06-20-55-34.gh-issue-130673.T3RSCI.rst

@@ -0,0 +1,2 @@
+Fix potential ``KeyError`` when handling object sections during JIT building
+process.

Tools/jit/_targets.py

@@ -330,7 +330,11 @@ def _handle_section(
         if section_type == "SHT_RELA":
             assert "SHF_INFO_LINK" in flags, flags
             assert not section["Symbols"]
-            value, base = group.symbols[section["Info"]]
+            maybe_symbol = group.symbols.get(section["Info"])
+            if maybe_symbol is None:
+                # These are relocations for a section we're not emitting. Skip:
+                return
+            value, base = maybe_symbol
             if value is _stencils.HoleValue.CODE:
                 stencil = group.code
             else:

Tools/jit/ignore-tests-emulated-linux.txt

@@ -25,6 +25,7 @@ test.test_pathlib.PosixPathTest.test_is_mount_root
 test.test_pathlib.test_pathlib.PathSubclassTest.test_is_mount_root
 test.test_pathlib.test_pathlib.PathTest.test_is_mount_root
 test.test_pathlib.test_pathlib.PosixPathTest.test_is_mount_root
+test.test_posix.PosixTester.test_fexecve
 test.test_posix.TestPosixSpawn.test_close_file
 test.test_posix.TestPosixSpawnP.test_close_file
 test.test_posixpath.PosixPathTest.test_ismount