ci: use config.mak for macOS Homebrew paths instead of make args

Shell quoting with make command-line variables is fragile — spaces in
CPPFLAGS/LDFLAGS caused make to interpret paths as options. Git's
Makefile auto-includes config.mak, so writing the paths there avoids
all quoting issues. Uses += to append to existing flags.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: clemlesne

.github/workflows/ci.yml

@@ -66,18 +66,19 @@ jobs:
           # On macOS, Homebrew keg-only packages (openssl, curl, gettext) are
           # not linked into the default search paths. Git's config.mak.uname
           # gained Homebrew auto-detection around v2.47, but older versions
-          # (2.34.1, 2.39.5) lack it. Git's Makefile overrides CFLAGS and
-          # LDFLAGS env vars, so we pass them on the make command line where
-          # they take precedence over Makefile assignments.
-          MAKE_ARGS="prefix=$HOME/git-install"
+          # (2.34.1, 2.39.5) lack it. Git's Makefile auto-includes config.mak,
+          # so we write the paths there to avoid shell quoting issues with
+          # make command-line variables.
           if [ "$RUNNER_OS" = "macOS" ]; then
             BREW_PREFIX=$(brew --prefix)
-            MAKE_ARGS="$MAKE_ARGS CPPFLAGS=-I${BREW_PREFIX}/opt/openssl/include\ -I${BREW_PREFIX}/opt/curl/include\ -I${BREW_PREFIX}/opt/expat/include\ -I${BREW_PREFIX}/opt/gettext/include"
-            MAKE_ARGS="$MAKE_ARGS LDFLAGS=-L${BREW_PREFIX}/opt/openssl/lib\ -L${BREW_PREFIX}/opt/curl/lib\ -L${BREW_PREFIX}/opt/expat/lib\ -L${BREW_PREFIX}/opt/gettext/lib"
+            cat > config.mak <<CFGEOF
+          CPPFLAGS += -I${BREW_PREFIX}/opt/openssl/include -I${BREW_PREFIX}/opt/curl/include -I${BREW_PREFIX}/opt/expat/include -I${BREW_PREFIX}/opt/gettext/include
+          LDFLAGS += -L${BREW_PREFIX}/opt/openssl/lib -L${BREW_PREFIX}/opt/curl/lib -L${BREW_PREFIX}/opt/expat/lib -L${BREW_PREFIX}/opt/gettext/lib
+          CFGEOF
           fi
 
-          make $MAKE_ARGS -j"$NPROC" all
-          make $MAKE_ARGS install
+          make prefix="$HOME/git-install" -j"$NPROC" all
+          make prefix="$HOME/git-install" install
 
       - name: Verify git build
         run: |

autoresearch-results.tsv

@@ -0,0 +1,18 @@
+# metric_direction: lower_is_better
+iteration	commit	metric	delta	guard	status	description
+0	034d5a3e	13.2	0.0	pass	baseline	initial state — indexing kubernetes in 13.2s
+1	838f0979	12.3	-0.9	pass	keep	pre-allocate postings builder maps with 200K capacity hint
+2	429d26fc	10.6	-1.7	pass	keep	merge postings and lastOffsets maps into single map with pointer values
+3	-	11.2	+0.6	-	discard	skip content-based enry.IsGenerated in rank (within noise, not worth behavior change)
+4	4013530b	9.9	-0.7	pass	keep	pre-allocate postingEntry data slice with 64-byte capacity
+5	-	10.4	+0.5	-	discard	use fixed-size array for rank vectors (larger struct offsets allocation savings)
+6	-	11.8	+1.9	-	discard	skip binary detection scan when SkipReason set (no-op, nil content check is already free)
+7	-	11.2	+1.3	-	discard	increase go-git LRU cache to 256MB (more GC pressure)
+8	-	10.3	+0.4	-	discard	slab-allocate postingEntry objects (data slices still dominate alloc)
+9	-	11.3	+1.4	-	discard	disable GOGC + 2GiB memlimit in builder (unreliable from library code)
+10	-	10.65	+0.75	-	discard	use slices.SortFunc for sorting (sort algo not the bottleneck, enry is)
+11	e3f2116f	8.3	-1.6	pass	keep	pipeline document creation with builder processing (goroutine pre-fetch)
+12	-	8.6	+0.3	-	discard	increase posting data capacity to 256 bytes (extra memory pressure)
+13	-	8.6	+0.3	-	discard	increase pipeline buffer to 512 (extra memory offsets sync savings)
+14	-	9.0	+0.7	-	discard	pre-allocate runeOffsets (4MB upfront increases memory pressure)
+15	-	9.6	+1.3	-	discard	reduce map capacity to 100K (more resizes hurt)