JMZ says:

   Add an emply MAIN__() function. This avoid an unresolved reference error
   during link phase when using fortran subroutines with non-fortran 'main()'.

Obtained from:  src/lib/libF77/MAIN.c rev 1.1 by jmz

1 files changed, 1 insertions, 0 deletions

diff --git a/gnu/lib/libg2c/MAIN.c b/gnu/lib/libg2c/MAIN.c
new file mode 100644
index 0000000..99b7114
--- /dev/null
+++ b/gnu/lib/libg2c/MAIN.c
@@ -0,0 +1 @@
+MAIN__(){}