fix build.zig not respecting --static

closes #2027

std/build.zig

@@ -1326,7 +1326,7 @@ pub const LibExeObjStep = struct {
             zig_args.append("--ver-patch") catch unreachable;
             zig_args.append(builder.fmt("{}", self.version.patch)) catch unreachable;
         }
-        if ((self.kind == Kind.Exe or self.kind == Kind.Test) and self.static) {
+        if (self.static) {
             zig_args.append("--static") catch unreachable;
         }
 

test/build_examples.zig

@@ -10,6 +10,7 @@ pub fn addCases(cases: *tests.BuildExamplesContext) void {
     cases.addBuildFile("test/standalone/main_pkg_path/build.zig");
     cases.addBuildFile("example/shared_library/build.zig");
     cases.addBuildFile("example/mix_o_files/build.zig");
+    cases.addBuildFile("test/standalone/static_c_lib/build.zig");
     if (builtin.os != builtin.Os.macosx) {
         // TODO https://github.com/ziglang/zig/issues/1126
         cases.addBuildFile("test/standalone/issue_339/build.zig");

test/standalone/static_c_lib/build.zig

@@ -0,0 +1,18 @@
+const Builder = @import("std").build.Builder;
+
+pub fn build(b: *Builder) void {
+    const mode = b.standardReleaseOptions();
+
+    const foo = b.addStaticLibrary("foo", null);
+    foo.addCSourceFile("foo.c", [][]const u8{});
+    foo.setBuildMode(mode);
+    foo.addIncludeDir(".");
+
+    const test_exe = b.addTest("foo.zig");
+    test_exe.setBuildMode(mode);
+    test_exe.linkLibrary(foo);
+    test_exe.addIncludeDir(".");
+
+    const test_step = b.step("test", "Test it");
+    test_step.dependOn(&test_exe.step);
+}

test/standalone/static_c_lib/foo.c

@@ -0,0 +1,4 @@
+#include "foo.h"
+uint32_t add(uint32_t a, uint32_t b) {
+    return a + b;
+}

test/standalone/static_c_lib/foo.h

@@ -0,0 +1,2 @@
+#include <stdint.h>
+uint32_t add(uint32_t a, uint32_t b);

test/standalone/static_c_lib/foo.zig

@@ -0,0 +1,8 @@
+const std = @import("std");
+const expect = std.testing.expect;
+const c = @cImport(@cInclude("foo.h"));
+
+test "C add" {
+    const result = c.add(1, 2);
+    expect(result == 3);
+}