diff --git a/compileopts/config.go b/compileopts/config.go
index a084403c..0da1a2b6 100644
--- a/compileopts/config.go
+++ b/compileopts/config.go
@@ -204,7 +204,8 @@ func (c *Config) CFlags() []string {
 	for _, flag := range c.Target.CFlags {
 		cflags = append(cflags, strings.ReplaceAll(flag, "{root}", goenv.Get("TINYGOROOT")))
 	}
-	if c.Target.Libc == "picolibc" {
+	switch c.Target.Libc {
+	case "picolibc":
 		root := goenv.Get("TINYGOROOT")
 		picolibcDir := filepath.Join(root, "lib", "picolibc", "newlib", "libc")
 		cflags = append(cflags,
@@ -213,6 +214,15 @@ func (c *Config) CFlags() []string {
 			"-Xclang", "-internal-isystem", "-Xclang", filepath.Join(picolibcDir, "tinystdio"),
 		)
 		cflags = append(cflags, "-I"+filepath.Join(root, "lib/picolibc-include"))
+	case "wasi-libc":
+		root := goenv.Get("TINYGOROOT")
+		cflags = append(cflags, "--sysroot="+root+"/lib/wasi-libc/sysroot")
+	case "":
+		// No libc specified, nothing to add.
+	default:
+		// Incorrect configuration. This could be handled in a better way, but
+		// usually this will be found by developers (not by TinyGo users).
+		panic("unknown libc: " + c.Target.Libc)
 	}
 	// Always emit debug information. It is optionally stripped at link time.
 	cflags = append(cflags, "-g")
diff --git a/targets/wasi.json b/targets/wasi.json
index 7826c48d..b7852ad4 100644
--- a/targets/wasi.json
+++ b/targets/wasi.json
@@ -6,9 +6,6 @@
 	"goarch":        "arm",
 	"linker":        "wasm-ld",
 	"libc":          "wasi-libc",
-	"cflags": [
-		"--sysroot={root}/lib/wasi-libc/sysroot"
-	],
 	"ldflags": [
 		"--allow-undefined",
 		"--stack-first",
diff --git a/targets/wasm.json b/targets/wasm.json
index bfffc005..047dd8c3 100644
--- a/targets/wasm.json
+++ b/targets/wasm.json
@@ -6,9 +6,6 @@
 	"goarch":        "wasm",
 	"linker":        "wasm-ld",
 	"libc":          "wasi-libc",
-	"cflags": [
-		"--sysroot={root}/lib/wasi-libc/sysroot"
-	],
 	"ldflags": [
 		"--allow-undefined",
 		"--stack-first",