python · brandtbucher · brandtbucher · brandtbucher · Oct 23, 2020 · brandtbucher
diff --git a/Python/ceval.c b/Python/ceval.c
diff --git a/Python/compile.c b/Python/compile.c
 static int compiler_enter_scope(struct compiler *, identifier, int, void *, int);
 static void compiler_free(struct compiler *);
 static basicblock *compiler_new_block(struct compiler *);
 static int compiler_next_instr(basicblock *);
 static int compiler_addop(struct compiler *, int);
 static int compiler_addop_i(struct compiler *, int, Py_ssize_t);
 static int compiler_addop_j(struct compiler *, int, basicblock *);
-static int compiler_error(struct compiler *, const char *);
+static int compiler_error(struct compiler *, const char *, ...);
diff --git a/Python/compile.c b/Python/compile.c
+#define CHECK(X)  \
+    if (!(X)) {   \
+        return 0; \
+    }
diff --git a/Python/compile.c b/Python/compile.c
+// To keep things simple, all compiler_pattern_* routines follow the convention
+// of preserving TOS (the subject for the given pattern) and pushing either True
+// (match) or False (no match) on top of it. We do this even for irrefutable
+// patterns; the idea is that it's much easier to smooth out any redundant
+// pushing, popping, and jumping in the peephole optimizer than to detect or
+// predict it here.
diff --git a/Python/ast_opt.c b/Python/ast_opt.c
+{
+    // Don't blindly optimize the pattern as an expr; it plays by its own rules!
+    // Currently, this is only used to form complex/negative numeric constants.
+    switch (node_->kind) {