diff --git a/libc-test/build.rs b/libc-test/build.rs
index 1173f665fb56..2927837976f9 100644
--- a/libc-test/build.rs
+++ b/libc-test/build.rs
@@ -42,6 +42,8 @@ fn do_cc() {
         || target.contains("l4re")
         || target.contains("android")
         || target.contains("emscripten")
+        || target.contains("solaris")
+        || target.contains("illumos")
     {
         cc::Build::new().file("src/sigrt.c").compile("sigrt");
     }
diff --git a/libc-test/semver/solarish.txt b/libc-test/semver/solarish.txt
index 3e672ebfb3f1..5603201070f3 100644
--- a/libc-test/semver/solarish.txt
+++ b/libc-test/semver/solarish.txt
@@ -16,6 +16,8 @@ LIO_WAIT
 LIO_WRITE
 PIPE_BUF
 SIGEV_PORT
+SIGRTMAX
+SIGRTMIN
 _POSIX_VDISABLE
 _ST_FSTYPSZ
 aio_cancel
diff --git a/libc-test/test/sigrt.rs b/libc-test/test/sigrt.rs
index 25e6ca4457b1..1f89ce042186 100644
--- a/libc-test/test/sigrt.rs
+++ b/libc-test/test/sigrt.rs
@@ -4,7 +4,9 @@
     target_os = "linux",
     target_os = "l4re",
     target_os = "android",
-    target_os = "emscripten"
+    target_os = "emscripten",
+    target_os = "solaris",
+    target_os = "illumos",
 ))]
 mod t {
     use libc;
diff --git a/src/unix/solarish/mod.rs b/src/unix/solarish/mod.rs
index 0b223cd982cf..70e549a1b5d8 100644
--- a/src/unix/solarish/mod.rs
+++ b/src/unix/solarish/mod.rs
@@ -2542,6 +2542,14 @@ f! {
 }
 
 safe_f! {
+    pub fn SIGRTMAX() -> c_int {
+        unsafe { crate::sysconf(_SC_SIGRT_MAX) as c_int }
+    }
+
+    pub fn SIGRTMIN() -> c_int {
+        unsafe { crate::sysconf(_SC_SIGRT_MIN) as c_int }
+    }
+
     pub {const} fn WIFEXITED(status: c_int) -> bool {
         (status & 0xFF) == 0
     }