POSIX: Add invocation of klee_init_env into wrapper before calling main

To enable the POSIX support, the former implementation instrumented the
main function and inserted a call to `klee_init_env` at the beginning.

This has multiple disadvantages:
* debugging information was not correctly propagated leaving the call to
`klee_init_env` without debug information
* the main function always required `int arg, char**` as part of the
function definition of `main`

Based on the new linking infrastructure, we can now add an additional
wrapper `__klee_posix_wraper(int, char**)` that gets always called when
POSIX support is enabled. It executes `klee_init_env` and after that
calls the `main` function.

Enabling POSIX support only requires the renaming of the user provided
`main` into `__klee_posix_wrapped_main` in addition to linking.

1 files changed, 2 insertions, 0 deletions

diff --git a/tools/klee-replay/klee_init_env.c b/tools/klee-replay/klee_init_env.c
index 229fe43d..5e9dd06c 100644
--- a/tools/klee-replay/klee_init_env.c
+++ b/tools/klee-replay/klee_init_env.c
@@ -1 +1,3 @@
 #include "../../runtime/POSIX/klee_init_env.c"
+
+int __klee_posix_wrapped_main(int argc, char **argv) { return 0; }