Enable -Wformat and -Wformat-security by default.
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -412,7 +412,7 @@ C ObjC C++ ObjC++ Var(warn_format_nonliteral) Warning LangEnabledBy(C ObjC C++ O
Warn about format strings that are not literals
Wformat-security
-C ObjC C++ ObjC++ Var(warn_format_security) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)
+C ObjC C++ ObjC++ Var(warn_format_security) Init(1) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)
Warn about possible security problems with format functions
Wformat-y2k
@@ -424,7 +424,7 @@ C ObjC C++ ObjC++ Var(warn_format_zero_length) Warning LangEnabledBy(C ObjC C++
Warn about zero-length formats
Wformat=
-C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_format) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)
+C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_format) Init(1) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)
Warn about printf/scanf/strftime/strfmon format string anomalies
Wignored-qualifiers
--- a/gcc/doc/gcc.info
+++ b/gcc/doc/gcc.info
@@ -3451,6 +3451,8 @@ compiler warns that an unrecognized option is present.
'-Wno-format-contains-nul', '-Wno-format-extra-args', and
'-Wno-format-zero-length'. '-Wformat' is enabled by '-Wall'.
+ This option is enabled by default in Alpine Linux.
+
'-Wno-format-contains-nul'
If '-Wformat' is specified, do not warn about format strings
that contain NUL bytes.
@@ -3496,6 +3498,8 @@ compiler warns that an unrecognized option is present.
future warnings may be added to '-Wformat-security' that are
not included in '-Wformat-nonliteral'.)
+ This option is enabled by default in Alpine Linux.
+
'-Wformat-y2k'
If '-Wformat' is specified, also warn about 'strftime' formats
that may yield only a two-digit year.