Separate compilation and linker phases (#376)

Separate between compilation and linker phases to allow deploy time
linking and back-porting era compiler changes to fix #91. Unlinked
contract binaries (caused by missing libraries or missing factory
dependencies in turn) are emitted as raw ELF object.

Few drive by fixes:
- #98
- A compiler panic on missing libraries definitions.
- Fixes some incosistent type forwarding in JSON output (empty string
vs. null object).
- Remove the unused fallback for size optimization setting.
- Remove the broken `--lvm-ir`  mode.
- CI workflow fixes.

---------

Signed-off-by: Cyrill Leutwiler <bigcyrill@hotmail.com>
Signed-off-by: xermicus <bigcyrill@hotmail.com>
Signed-off-by: xermicus <cyrill@parity.io>

crates/resolc/src/missing_libraries.rs

@@ -1,22 +1,21 @@
 //! The missing Solidity libraries.
 
 use std::collections::BTreeMap;
-use std::collections::HashSet;
+use std::collections::BTreeSet;
 
 use revive_solc_json_interface::SolcStandardJsonOutput;
 
 use crate::solc::version::Version as SolcVersion;
-use crate::ResolcVersion;
 
 /// The missing Solidity libraries.
 pub struct MissingLibraries {
     /// The missing libraries.
-    pub contract_libraries: BTreeMap<String, HashSet<String>>,
+    pub contract_libraries: BTreeMap<String, BTreeSet<String>>,
 }
 
 impl MissingLibraries {
     /// A shortcut constructor.
-    pub fn new(contract_libraries: BTreeMap<String, HashSet<String>>) -> Self {
+    pub fn new(contract_libraries: BTreeMap<String, BTreeSet<String>>) -> Self {
         Self { contract_libraries }
     }
 
@@ -25,27 +24,19 @@ impl MissingLibraries {
         mut self,
         standard_json: &mut SolcStandardJsonOutput,
         solc_version: &SolcVersion,
-    ) -> anyhow::Result<()> {
-        let contracts = match standard_json.contracts.as_mut() {
-            Some(contracts) => contracts,
-            None => return Ok(()),
-        };
-
-        for (path, contracts) in contracts.iter_mut() {
-            for (name, contract) in contracts.iter_mut() {
+    ) {
+        for (path, file) in standard_json.contracts.iter_mut() {
+            for (name, contract) in file.iter_mut() {
                 let full_name = format!("{path}:{name}");
                 let missing_libraries = self.contract_libraries.remove(full_name.as_str());
 
                 if let Some(missing_libraries) = missing_libraries {
-                    contract.missing_libraries = Some(missing_libraries);
+                    contract.missing_libraries = missing_libraries;
                 }
             }
         }
 
         standard_json.version = Some(solc_version.default.to_string());
         standard_json.long_version = Some(solc_version.long.to_owned());
-        standard_json.revive_version = Some(ResolcVersion::default().long);
-
-        Ok(())
     }
 }