Enable clang and gcc cast-align[=strict] warning in CI.

Author: mbroz

.gitlab/ci/clang-Wall

@@ -15,12 +15,10 @@ CLANG="clang${COMPILER_VERSION:+-$COMPILER_VERSION}"
 #PEDANTIC="-pedantic -std=gnu99 -Wno-variadic-macros"
 #CONVERSION="-Wconversion"
 
-# FIXME
-# -Wcast-align
-
 EXTRA="\
  -Wextra \
  -Wsign-compare \
+ -Wcast-align
  -Werror-implicit-function-declaration \
  -Wpointer-arith \
  -Wwrite-strings \

.gitlab/ci/gcc-Wall

@@ -50,7 +50,7 @@ exec $GCC $PEDANTIC $CONVERSION \
 	-Wnested-externs \
 	-Wcomment \
 	-Winline \
-	-Wcast-align \
+	-Wcast-align=strict \
 	-Wcast-qual \
 	-Wredundant-decls $EXTRA \
 	"$@"