README: use upstream Zig

stage0/README.md

@@ -18,25 +18,25 @@ This is written with help from LLM:
 
 Quick test:
 
-    ./zig-out/bin/zig build fmt-zig0 test-zig0
+    zig build fmt-zig0 test-zig0
 
 Static analysis (takes a while, run separately):
 
-    ./zig-out/bin/zig build lint-zig0
+    zig build lint-zig0
 
 More elaborate (tries all compilers + static analysis + ReleaseSafe):
 
-    ./zig-out/bin/zig build all-zig0 -Doptimize=ReleaseSafe
+    zig build all-zig0 -Doptimize=ReleaseSafe
 
 Most elaborate, takes >10m:
 
-    ./zig-out/bin/zig build all-zig0 -Doptimize=ReleaseSafe -Dvalgrind |& grep -v Warning
+    zig build all-zig0 -Doptimize=ReleaseSafe -Dvalgrind |& grep -v Warning
 
 # Debugging tips
 
 Test runs infinitely? Build the test program executable:
 
-    $ ./zig-out/bin/zig build test-zig0 -Dzig0-no-exec
+    $ zig build test-zig0 -Dzig0-no-exec
 
 And then run it, capturing the stack trace:
 
@@ -70,16 +70,3 @@ in `astgen_test.zig` skips float128 payloads to account for this.
 
 Previous approach used `__float128`/`strtof128` (GCC/glibc extensions) for
 full precision, but these are not portable to TCC and other C11 compilers.
-
-# Rebuilding zig
-
-If you need to rebuild zig-out/bin/zig for some reason, here's how:
-
-```
-~/code/zig-bootstrap/out-0.15.2/zig-x86_64-linux-musl-x86_64_v3/zig build \
-    --zig-lib-dir lib/ -Dtarget=x86_64-linux-musl -Dcpu=x86_64_v3 \
-    -Dstatic-llvm --search-prefix \
-    $HOME/code/zig-bootstrap/out-0.15.2/x86_64-linux-musl-x86_64_v3/ \
-    -Ddebug-extensions=true -Dlog=false -Doptimize=ReleaseSafe
-
-```