Revert Makefile to original working flags

Revert to the simple -Wall -Wextra -Werror -pedantic -std=c99
flags that work across all platforms.  The extra hardening and
warning flags caused build failures due to differences between
GCC versions, distro-specific compiler specs, and platform
feature availability.

Author: renaudallard

.github/workflows/build.yml

@@ -66,14 +66,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Build
-        run: |
-          if ! make 2>&1; then
-            echo "## Build Failed" >> $GITHUB_STEP_SUMMARY
-            echo '```' >> $GITHUB_STEP_SUMMARY
-            make 2>&1 >> $GITHUB_STEP_SUMMARY || true
-            echo '```' >> $GITHUB_STEP_SUMMARY
-            exit 1
-          fi
+        run: make
 
       - name: Verify binary
         run: ./thinproxy -V
@@ -133,14 +126,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Build
-        run: |
-          if ! make 2>&1; then
-            echo "## Build Failed" >> $GITHUB_STEP_SUMMARY
-            echo '```' >> $GITHUB_STEP_SUMMARY
-            make 2>&1 >> $GITHUB_STEP_SUMMARY || true
-            echo '```' >> $GITHUB_STEP_SUMMARY
-            exit 1
-          fi
+        run: make
 
       - name: Verify binary
         run: ./thinproxy -V

Makefile

@@ -1,10 +1,6 @@
 CC ?=		cc
 CFLAGS ?=	-O2 -pipe
-WARNINGS =	-Wall -Wextra -Werror -pedantic -std=c99 \
-		-Wformat -Wformat-security \
-		-Wshadow -Wstrict-prototypes -Wmissing-prototypes \
-		-Wold-style-definition -Wimplicit-fallthrough
-HARDENING =	-fstack-protector-strong -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2
+CFLAGS +=	-Wall -Wextra -Werror -pedantic -std=c99
 
 PREFIX ?=	/usr/local
 BINDIR ?=	$(PREFIX)/bin
@@ -14,7 +10,7 @@ UNITDIR ?=	/lib/systemd/system
 all: thinproxy
 
 thinproxy: thinproxy.c
-	$(CC) $(CFLAGS) $(WARNINGS) $(HARDENING) $(LDFLAGS) -o $@ thinproxy.c
+	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ thinproxy.c
 
 install: thinproxy
 	install -d $(DESTDIR)$(BINDIR)