diff --git a/dev-lang/cc65/cc65-2.19-r3.ebuild b/dev-lang/cc65/cc65-2.19-r3.ebuild
index 101856cdd6..c365d5163e 100644
--- a/dev-lang/cc65/cc65-2.19-r3.ebuild
+++ b/dev-lang/cc65/cc65-2.19-r3.ebuild
@@ -14,6 +14,11 @@ SLOT="0"
 KEYWORDS="~amd64"
 
 src_compile() {
+	ewarn "According to an upstream maintainer, cc65 has a tendency to"
+	ewarn "\"fail randomly\" when using \`make -j' to build in parallel."
+	ewarn "If compiling this package fails, and you have parallel jobs"
+	ewarn "enabled, try again with \`MAKEOPTS+=-j1' to disable them."
+
 	emake CC="$(tc-getCC)" AR="$(tc-getAR)" PREFIX="${EPREFIX}/usr"
 }
 
diff --git a/dev-lang/cc65/cc65-9999-r1.ebuild b/dev-lang/cc65/cc65-9999-r1.ebuild
index dc3fbf25fd..32270f99b6 100644
--- a/dev-lang/cc65/cc65-9999-r1.ebuild
+++ b/dev-lang/cc65/cc65-9999-r1.ebuild
@@ -13,6 +13,11 @@ LICENSE="ZLIB"
 SLOT="0"
 
 src_compile() {
+	ewarn "According to an upstream maintainer, cc65 has a tendency to"
+	ewarn "\"fail randomly\" when using \`make -j' to build in parallel."
+	ewarn "If compiling this package fails, and you have parallel jobs"
+	ewarn "enabled, try again with \`MAKEOPTS+=-j1' to disable them."
+
 	emake CC="$(tc-getCC)" AR="$(tc-getAR)" PREFIX="${EPREFIX}/usr"
 }