1 files changed, 1 insertions, 1 deletions
diff --git a/etc/sh/rc b/etc/sh/rc
index aa0ee5a..1a77b67 100644
--- a/etc/sh/rc
+++ b/etc/sh/rc
@@ -76,7 +76,7 @@ N_PROCS=$(($(nproc) * 2 + 1))
 GUILE_EFFECTIVE_VERSION="$(guile -c '(display (effective-version))')"
 export MAKEFLAGS="-j $N_PROCS"
 export GOPATH="$SRC/go"
-export CFLAGS='-std=c99 -Wall -Wextra -Wpedantic -O0 -g -flto -Werror'
+export CFLAGS='-D_POSIX_C_SOURCE=200809L -std=c99 -Wall -Wextra -Wpedantic -O0 -g -flto -Werror'
 export CC=gcc
 export AR=gcc-ar
 export LEX=flex