* configure.ac: Invoke gl_ASSERT_NO_GNULIB_POSIXCHECK.
(--enable-gcc-warnings): Change help message.
(gl_GCC_VERSION_IFELSE): New macro.
Do not omit -Wunused-macros for main code.
Adjust other -W options as per coreutils.
* lib/Makefile.am (AM_CFLAGS): Use GNULIB_WARN_CFLAGS, not WARN_CFLAGS.
* unlzw.c (REGISTERS, REG1, REG2, ..., REG16): Remove.
All uses removed. These provoked -Wunused-macros warnings.
This sort of fiddling with registers hasn't been needed for years.
---
configure.ac | 71 +++++++++++++++++++++++++++------
lib/Makefile.am | 2 +-
unlzw.c | 120 +++++++++-----------------------------------------------
3 files changed, 78 insertions(+), 115 deletions(-)
diff --git a/configure.ac b/configure.ac
index 64112da..a73d5a5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -30,6 +30,20 @@ AC_CONFIG_HEADERS([lib/config.h:lib/config.hin])
AM_INIT_AUTOMAKE([1.11 dist-xz color-tests parallel-tests])
AM_SILENT_RULES([yes]) # make --enable-silent-rules the default.
+dnl POSIXCHECK is worthwhile for maintainers, but adds several seconds
+dnl (more than 10% execution time) to ./configure, with no benefit for
+dnl most users. Using it to look for bugs requires:
+dnl GNULIB_POSIXCHECK=1 autoreconf -f
+dnl ./configure
+dnl make
+dnl make -C src clean
+dnl make CFLAGS=-DGNULIB_POSIXCHECK=1
+dnl FIXME: Once we figure out how to avoid false positives, we should
+dnl have 'make my-distcheck' in dist-check.mk exercise this.
+m4_syscmd([test "${GNULIB_POSIXCHECK+set}" = set])
+m4_if(m4_sysval, [0], [], [dnl
+gl_ASSERT_NO_GNULIB_POSIXCHECK])
+
AC_PROG_CC_STDC
AM_PROG_CC_C_O
AC_PROG_CPP
@@ -45,7 +59,7 @@ gl_INIT
AC_ARG_ENABLE([gcc-warnings],
[AS_HELP_STRING([--enable-gcc-warnings],
- [turn on lots of GCC warnings (for developers)])],
+ [turn on many GCC warnings (for developers; best with GNU make)])],
[case $enableval in
yes|no) ;;
*) AC_MSG_ERROR([bad value $enableval for gcc-warnings option]) ;;
@@ -58,6 +72,24 @@ AC_ARG_ENABLE([gcc-warnings],
fi]
)
+# gl_GCC_VERSION_IFELSE([major], [minor], [run-if-found], [run-if-not-found])
+# ------------------------------------------------
+# If $CPP is gcc-MAJOR.MINOR or newer, then run RUN-IF-FOUND.
+# Otherwise, run RUN-IF-NOT-FOUND.
+AC_DEFUN([gl_GCC_VERSION_IFELSE],
+ [AC_PREPROC_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[
+#if ($1) < __GNUC__ || (($1) == __GNUC__ && ($2) <= __GNUC_MINOR__)
+/* ok */
+#else
+# error "your version of gcc is older than $1.$2"
+#endif
+ ]]),
+ ], [$3], [$4])
+ ]
+)
+
if test "$gl_gcc_warnings" = yes; then
gl_WARN_ADD([-Werror], [WERROR_CFLAGS])
AC_SUBST([WERROR_CFLAGS])
@@ -90,26 +122,34 @@ if test "$gl_gcc_warnings" = yes; then
nw="$nw -Wmissing-format-attribute" # copy.c
nw="$nw -Wunsafe-loop-optimizations" # a few src/*.c
nw="$nw -Winline" # system.h's
readdir_ignoring_dot_and_dotdot
- nw="$nw -Wstrict-overflow" # expr.c, pr.c, tr.c, factor.c
- # initial problems in gzip
+
+ # Warnings that gzip runs afoul of but coreutils does not.
nw="$nw -Wold-style-definition"
nw="$nw -Wshadow"
- nw="$nw -Wunused-macros"
- # ?? -Wstrict-overflow
+ nw="$nw -Wstrict-overflow"
+
+ # Using -Wstrict-overflow is a pain, but the alternative is worse.
+ # For an example, see the code that provoked this report:
+ # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33498
+ # Code like that still infloops with gcc-4.6.0 and -O2. Scary indeed.
gl_MANYWARN_ALL_GCC([ws])
gl_MANYWARN_COMPLEMENT([ws], [$ws], [$nw])
for w in $ws; do
gl_WARN_ADD([$w])
done
- gl_WARN_ADD([-Wno-missing-field-initializers]) # We need this one
gl_WARN_ADD([-Wno-sign-compare]) # Too many warnings for now
- gl_WARN_ADD([-Wno-pointer-sign]) # Too many warnings for now
gl_WARN_ADD([-Wno-unused-parameter]) # Too many warnings for now
- gl_WARN_ADD([-Wno-overflow]) # util.c
- gl_WARN_ADD([-Wno-type-limits]) # util.c
+ gl_WARN_ADD([-Wsuggest-attribute=const])
+ gl_WARN_ADD([-Wsuggest-attribute=noreturn])
gl_WARN_ADD([-Wno-format-nonliteral])
- gl_WARN_ADD([-Wno-unsuffixed-float-constants])
+
+ # Enable this warning only with gcc-4.7 and newer. With 4.6.2 20111027,
+ # it suggests test.c's advance function may be pure, even though it
+ # increments a global variable. Oops.
+ # Normally we'd write code to test for the precise failure, but that
+ # requires a relatively large input to make gcc exhibit the failure.
+ gl_GCC_VERSION_IFELSE([4], [7], [gl_WARN_ADD([-Wsuggest-attribute=pure])])
# In spite of excluding -Wlogical-op above, it is enabled, as of
# gcc 4.5.0 20090517, and it provokes warnings in cat.c, dd.c, truncate.c
@@ -121,14 +161,21 @@ if test "$gl_gcc_warnings" = yes; then
AC_SUBST([WARN_CFLAGS])
AC_DEFINE([lint], [1], [Define to 1 if the compiler is checking for lint.])
- AC_DEFINE([_FORTIFY_SOURCE], [2],
- [enable compile-time and run-time bounds-checking, and some warnings])
+ AH_VERBATIM([FORTIFY_SOURCE],
+ [/* Enable compile-time and run-time bounds-checking, and some warnings,
+ without upsetting glibc 2.15+. */
+ #if !defined _FORTIFY_SOURCE && defined __OPTIMIZE__ && __OPTIMIZE__
+ # define _FORTIFY_SOURCE 2
+ #endif
+ ])
AC_DEFINE([GNULIB_PORTCHECK], [1], [enable some gnulib portability checks])
# We use a slightly smaller set of warning options for lib/.
# Remove the following and save the result in GNULIB_WARN_CFLAGS.
nw=
+ nw="$nw -Wstrict-overflow"
nw="$nw -Wuninitialized"
+ nw="$nw -Wunused-macros"
nw="$nw -Wmissing-prototypes"
nw="$nw -Wold-style-definition"
gl_MANYWARN_COMPLEMENT([GNULIB_WARN_CFLAGS], [$WARN_CFLAGS], [$nw])
diff --git a/lib/Makefile.am b/lib/Makefile.am
index f31fd9a..5bc40eb 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -29,7 +29,7 @@ include gnulib.mk
libgzip_a_LIBADD += $(LIBOBJS)
libgzip_a_DEPENDENCIES += $(LIBOBJS)
-AM_CFLAGS += $(WARN_CFLAGS) $(WERROR_CFLAGS)
+AM_CFLAGS += $(GNULIB_WARN_CFLAGS) $(WERROR_CFLAGS)
match.$(OBJEXT): match.c
$(AM_V_GEN)cp $(srcdir)/match.c _match.S
diff --git a/unlzw.c b/unlzw.c
index 63f941c..994a86b 100644
--- a/unlzw.c
+++ b/unlzw.c
@@ -24,90 +24,6 @@ typedef unsigned long cmp_code_int;
#define MAXCODE(n) (1L << (n))
-#ifndef REGISTERS
-# define REGISTERS 2
-#endif
-#define REG1
-#define REG2
-#define REG3
-#define REG4
-#define REG5
-#define REG6
-#define REG7
-#define REG8
-#define REG9
-#define REG10
-#define REG11
-#define REG12
-#define REG13
-#define REG14
-#define REG15
-#define REG16
-#if REGISTERS >= 1
-# undef REG1
-# define REG1 register
-#endif
-#if REGISTERS >= 2
-# undef REG2
-# define REG2 register
-#endif
-#if REGISTERS >= 3
-# undef REG3
-# define REG3 register
-#endif
-#if REGISTERS >= 4
-# undef REG4
-# define REG4 register
-#endif
-#if REGISTERS >= 5
-# undef REG5
-# define REG5 register
-#endif
-#if REGISTERS >= 6
-# undef REG6
-# define REG6 register
-#endif
-#if REGISTERS >= 7
-# undef REG7
-# define REG7 register
-#endif
-#if REGISTERS >= 8
-# undef REG8
-# define REG8 register
-#endif
-#if REGISTERS >= 9
-# undef REG9
-# define REG9 register
-#endif
-#if REGISTERS >= 10
-# undef REG10
-# define REG10 register
-#endif
-#if REGISTERS >= 11
-# undef REG11
-# define REG11 register
-#endif
-#if REGISTERS >= 12
-# undef REG12
-# define REG12 register
-#endif
-#if REGISTERS >= 13
-# undef REG13
-# define REG13 register
-#endif
-#if REGISTERS >= 14
-# undef REG14
-# define REG14 register
-#endif
-#if REGISTERS >= 15
-# undef REG15
-# define REG15 register
-#endif
-#if REGISTERS >= 16
-# undef REG16
-# define REG16 register
-#endif
-
#ifndef BYTEORDER
# define BYTEORDER 0000
#endif
@@ -146,7 +62,7 @@ union bytes {
}
#else
# define input(b,o,c,n,m){ \
- REG1 char_type *p = &(b)[(o)>>3]; \
+ char_type *p = &(b)[(o)>>3]; \
(c) = ((((long)(p[0]))|((long)(p[1])<<8)| \
((long)(p[2])<<16))>>((o)&0x7))&(m); \
(o) += (n); \
@@ -183,21 +99,21 @@ int block_mode = BLOCK_MODE; /* block compress mode -C
compatible with 2.0 */
int unlzw(in, out)
int in, out; /* input and output file descriptors */
{
- REG2 char_type *stackp;
- REG3 code_int code;
- REG4 int finchar;
- REG5 code_int oldcode;
- REG6 code_int incode;
- REG7 long inbits;
- REG8 long posbits;
- REG9 int outpos;
-/* REG10 int insize; (global) */
- REG11 unsigned bitmask;
- REG12 code_int free_ent;
- REG13 code_int maxcode;
- REG14 code_int maxmaxcode;
- REG15 int n_bits;
- REG16 int rsize;
+ char_type *stackp;
+ code_int code;
+ int finchar;
+ code_int oldcode;
+ code_int incode;
+ long inbits;
+ long posbits;
+ int outpos;
+/* int insize; (global) */
+ unsigned bitmask;
+ code_int free_ent;
+ code_int maxcode;
+ code_int maxmaxcode;
+ int n_bits;
+ int rsize;
#ifdef MAXSEG_64K
tab_prefix[0] = tab_prefix0;
@@ -235,7 +151,7 @@ int unlzw(in, out)
tab_suffixof(code) = (char_type)code;
}
do {
- REG1 int i;
+ int i;
int e;
int o;
@@ -329,7 +245,7 @@ int unlzw(in, out)
/* And put them out in forward order */
{
- REG1 int i;
+ int i;
if (outpos+(i = (de_stack-stackp)) >= OUTBUFSIZ) {
do {
--
1.7.11.7
