diff --git a/rust.changes b/rust.changes
index ccdc678..683fdbb 100644
--- a/rust.changes
+++ b/rust.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Thu Feb 28 17:08:08 UTC 2019 - Federico Mena Quintero <federico@suse.com>
+
+- Use cmake3, not cmake, in SLE-12 SP2 and earlier.  The stock cmake
+  package there was 2.x, and building llvm requires cmake 3.5.
+
 -------------------------------------------------------------------
 Wed Feb 27 21:39:35 UTC 2019 - jones_ld@protonmail.com
 
diff --git a/rust.spec b/rust.spec
index f8c59f5..48e9149 100644
--- a/rust.spec
+++ b/rust.spec
@@ -78,7 +78,6 @@
 # Use hardening ldflags.
 %global rustflags -Clink-arg=-Wl,-z,relro,-z,now
 
-
 Name:           rust
 Version:        1.32.0
 Release:        0
@@ -98,7 +97,14 @@ Source106:      %{dl_url}/rust-%{prev_rust}-powerpc64le-unknown-linux-gnu.tar.xz
 Source107:      %{dl_url}/rust-%{prev_rust}-s390x-unknown-linux-gnu.tar.xz
 # PATCH-FIX-OPENSUSE: edit src/librustc_llvm/build.rs to ignore GCC incompatible flag
 Patch0:         ignore-Wstring-conversion.patch
+# Leap 42 to 42.3, SLE12 SP1, SP2
+%if 0%{?sle_version} >= 120000 && 0%{?sle_version} < 123000
+# In these distros cmake is 2.x, so we need cmake3 for building llvm.
+BuildRequires:  cmake3
+%else
+# cmake got upgraded to 3.5 in SLE-12 SP2
 BuildRequires:  cmake
+%endif
 BuildRequires:  curl
 BuildRequires:  fdupes
 BuildRequires:  gcc-c++