check only that symbol names are deterministic

Full binary reproducible builds are not possible on all platforms
because linker injects a certain amount of randomness, apparently. Or,
at minimum, they don't work reliably yet.

Author: nikomatsakis

src/test/run-make/reproducible-build/Makefile

@@ -3,12 +3,18 @@ all:
 	$(RUSTC) reproducible-build-aux.rs
 	$(RUSTC) reproducible-build.rs -o"$(TMPDIR)/reproducible-build1"
 	$(RUSTC) reproducible-build.rs -o"$(TMPDIR)/reproducible-build2"
-	cmp "$(TMPDIR)/reproducible-build1" "$(TMPDIR)/reproducible-build2" || exit 1
+	nm "$(TMPDIR)/reproducible-build1" | sort > "$(TMPDIR)/reproducible-build1.nm"
+	nm "$(TMPDIR)/reproducible-build2" | sort > "$(TMPDIR)/reproducible-build2.nm"
+	cmp "$(TMPDIR)/reproducible-build1.nm" "$(TMPDIR)/reproducible-build2.nm" || exit 1
 	$(RUSTC) reproducible-build-aux.rs -g
 	$(RUSTC) reproducible-build.rs -g -o"$(TMPDIR)/reproducible-build1-debug"
 	$(RUSTC) reproducible-build.rs -g -o"$(TMPDIR)/reproducible-build2-debug"
-	cmp "$(TMPDIR)/reproducible-build1-debug" "$(TMPDIR)/reproducible-build2-debug" || exit 1
+	nm "$(TMPDIR)/reproducible-build1-debug" | sort > "$(TMPDIR)/reproducible-build1-debug.nm"
+	nm "$(TMPDIR)/reproducible-build2-debug" | sort > "$(TMPDIR)/reproducible-build2-debug.nm"
+	cmp "$(TMPDIR)/reproducible-build1-debug.nm" "$(TMPDIR)/reproducible-build2-debug.nm" || exit 1
 	$(RUSTC) reproducible-build-aux.rs -O
 	$(RUSTC) reproducible-build.rs -O -o"$(TMPDIR)/reproducible-build1-opt"
 	$(RUSTC) reproducible-build.rs -O -o"$(TMPDIR)/reproducible-build2-opt"
-	cmp "$(TMPDIR)/reproducible-build1-opt" "$(TMPDIR)/reproducible-build2-opt" || exit 1
+	nm "$(TMPDIR)/reproducible-build1-opt" | sort > "$(TMPDIR)/reproducible-build1-opt.nm"
+	nm "$(TMPDIR)/reproducible-build2-opt" | sort > "$(TMPDIR)/reproducible-build2-opt.nm"
+	cmp "$(TMPDIR)/reproducible-build1-opt.nm" "$(TMPDIR)/reproducible-build2-opt.nm" || exit 1