gcc-plugins/stackleak: Avoid assignment for unused macro argument (8d97fb39) · Commits · 戴 / test

With GCC version >= 8, the cgraph_create_edge() macro argument using "frequency" goes unused. Instead of assigning a temporary variable for the argument, pass the compute_call_stmt_bb_frequency() call directly as the macro argument so that it will just not be called when it is not wanted by the macros. Silences the warning: scripts/gcc-plugins/stackleak_plugin.c:54:6: warning: variable ‘frequency’ set but not used [-Wunused-but-set-variable] Now builds cleanly with gcc-7 and gcc-9. Both boot and pass STACKLEAK_ERASING LKDTM test. Signed-off-by:

Kees Cook <keescook@chromium.org>

scripts/gcc-plugins/stackleak_plugin.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -51,7 +51,6 @@ static void stackleak_add_track_stack(gimple_stmt_iterator *gsi, bool after)
		gimple stmt;
		gcall *stackleak_track_stack;
		cgraph_node_ptr node;
		int frequency;
		basic_block bb;

		/* Insert call to void stackleak_track_stack(void) */
		@@ -68,9 +67,9 @@ static void stackleak_add_track_stack(gimple_stmt_iterator *gsi, bool after)
		bb = gimple_bb(stackleak_track_stack);
		node = cgraph_get_create_node(track_function_decl);
		gcc_assert(node);
		frequency = compute_call_stmt_bb_frequency(current_function_decl, bb);
		cgraph_create_edge(cgraph_get_node(current_function_decl), node,
		stackleak_track_stack, bb->count, frequency);
		stackleak_track_stack, bb->count,
		compute_call_stmt_bb_frequency(current_function_decl, bb));
		}

		static bool is_alloca(gimple stmt)

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