build: show stderr by default

Also added: `-d:cwarnings` and `-d:limitStackUsage`

config.nims

@@ -13,6 +13,10 @@ switch("nimcache", nimCachePath)
 # `-flto` gives a significant improvement in processing speed, specially hash tree and state transition (basically any CPU-bound code implemented in nim)
 # With LTO enabled, optimization flags should be passed to both compiler and linker!
 if defined(release) and not defined(disableLTO):
+  # "-w" is not passed to the compiler during linking, so we need to disable
+  # some warnings by hand.
+  switch("passL", "-Wno-stringop-overflow -Wno-stringop-overread")
+
   if defined(macosx): # Clang
     switch("passC", "-flto=thin")
     switch("passL", "-flto=thin -Wl,-object_path_lto," & nimCachePath & "/lto")
@@ -26,6 +30,23 @@ if defined(release) and not defined(disableLTO):
     # used for static libraries.
     discard
 
+# show C compiler warnings
+if defined(cwarnings):
+  let common_gcc_options = "-Wno-discarded-qualifiers -Wno-incompatible-pointer-types"
+  if defined(windows):
+    put("gcc.options.always", "-mno-ms-bitfields " & common_gcc_options)
+    put("clang.options.always", "-mno-ms-bitfields " & common_gcc_options)
+  else:
+    put("gcc.options.always", common_gcc_options)
+    put("clang.options.always", common_gcc_options)
+
+if defined(limitStackUsage):
+  # This limits stack usage of each individual function to 1MB - the option is
+  # available on some GCC versions but not all - run with `-d:limitStackUsage`
+  # and look for .su files in "./nimcache/" that list the stack size of each function
+  switch("passC", "-fstack-usage -Werror=stack-usage=1048576")
+  switch("passL", "-fstack-usage -Werror=stack-usage=1048576")
+
 if defined(windows):
   # disable timestamps in Windows PE headers - https://wiki.debian.org/ReproducibleBuilds/TimestampsInPEBinaries
   switch("passL", "-Wl,--no-insert-timestamp")

docs/the_nimbus_book/src/developers.md

@@ -139,7 +139,19 @@ make NIMFLAGS="-d:disableMarchNative" nimbus_beacon_node
 make NIMFLAGS="-d:disableLTO" nimbus_beacon_node
 ```
 
-- build a static binary
+- show C compiler warnings:
+
+```bash
+make NIMFLAGS="-d:cwarnings" nimbus_beacon_node
+```
+
+- limit stack usage to 1 MiB per C function (static analysis - see the [GCC docs](https://gcc.gnu.org/onlinedocs/gnat_ugn/Static-Stack-Usage-Analysis.html); if LTO is enabled, it works without `-d:cwarnings`):
+
+```bash
+make NIMFLAGS="-d:limitStackUsage" nimbus_beacon_node
+```
+
+- build a static binary:
 
 ```bash
 make NIMFLAGS="--passL:-static" nimbus_beacon_node
@@ -151,18 +163,12 @@ make NIMFLAGS="--passL:-static" nimbus_beacon_node
 make publish-book
 ```
 
-- create a binary distribution
+- create a binary distribution:
 
 ```bash
 make dist
 ```
 
-- test the binaries
-
-```bash
-make dist-test
-```
-
 ## Multi-client interop scripts
 
 [This repository](https://github.com/eth2-clients/multinet) contains a set of scripts used by the client implementation teams to test interop between the clients (in certain simplified scenarios). It mostly helps us find and debug issues.

scripts/compile_nim_program.sh

@@ -23,7 +23,8 @@ PROJECT_NAME="$(basename ${SOURCE%.nim})"
 # LTO on macOS, in "config.nims"
 nim c --compileOnly -o:build/${BINARY} "$@" -d:nimCachePathOverride=nimcache/release/${BINARY} "${SOURCE}"
 build/generate_makefile "nimcache/release/${BINARY}/${PROJECT_NAME}.json" "nimcache/release/${BINARY}/${BINARY}.makefile"
-[[ "$V" == "0" ]] && exec &>/dev/null
+# Don't swallow stderr, in case it's important.
+[[ "$V" == "0" ]] && exec >/dev/null
 "${MAKE}" -f "nimcache/release/${BINARY}/${BINARY}.makefile" --no-print-directory build
 
 if uname | grep -qi darwin || [[ -n "${FORCE_DSYMUTIL}" ]]; then

vendor/nimbus-build-system

@@ -1 +1 @@
-Subproject commit 9d6b4b6e98515af8248127f51889c24308006096
+Subproject commit 5fbffb22859a85aa0dc3e9238cc03d92ab197682