Deal with some gcc-10 warnings and clang-10

ChangeLog

@@ -8,7 +8,8 @@
 	- Minor change of the proto wire format (extension w/ deprecation) to
 	  allow distinction between empty and unset/equal effective keywords
 	- Manpage typo fixes, and clarify that --proto is setting independent
-	- The second part of the eix-0.34.3 patch was not in the repo.
+	- Deal with some new gcc-10 warnings and clang-10
+	- Put originally missing second part of eix-0.34.3 patch into repo
 
 *eix-0.34.3
 	Martin Väth <martin at mvath.de>:

config.h.in

@@ -437,9 +437,18 @@
 /* Define if cache method sqlite is wanted */
 #undef WITH_SQLITE
 
+/* Define if GCC diagnostic -Wsuggest-attribute=const can be used */
+#undef WSUGGEST_ATTRIBUTE_CONST
+
+/* Define if GCC diagnostic -Wsuggest-attribute=pure can be used */
+#undef WSUGGEST_ATTRIBUTE_PURE
+
 /* Define if GCC diagnostic -Wsuggest-final-methods can be used */
 #undef WSUGGEST_FINAL_METHODS
 
+/* Define if GCC diagnostic -Wzero-as-null-pointer-constant can be used */
+#undef WZERO_AS_NULL_POINTER_CONSTANT
+
 /* Enable large inode numbers on Mac OS X 10.5.  */
 #ifndef _DARWIN_USE_64_BIT_INODE
 # define _DARWIN_USE_64_BIT_INODE 1

configure.ac

@@ -461,7 +461,6 @@ dnl -Wzero-as-null-pointer-constant makes sense only with new dialects
 	MV_ADDFLAGS([my_cxxadd], [CXXFLAGS], [AC_COMPILE_IFELSE], [ \
 			-fno-common \
 			-funsigned-char \
-			-fdirectives-only \
 			-ftracer \
 			-fconcepts \
 		], [$my_cxxfatal], [$CPPFLAGS], [:])
@@ -478,7 +477,7 @@ dnl -Wzero-as-null-pointer-constant makes sense only with new dialects
 			-Wmissing-include-dirs \
 			-Wswitch-default \
 			-Wstrict-aliasing=1 \
-			-Wstrict-overflow=5 \
+			-Wstrict-overflow \
 			-Wfloat-equal \
 			-Wundef \
 			-Wshadow \
@@ -534,7 +533,6 @@ dnl -Wzero-as-null-pointer-constant makes sense only with new dialects
 			-Wduplicated-branches \
 			-Wduplicated-cond \
 			-Wstringop-truncation \
-			-Wno-c++1z-extensions \
 		], [$my_cxxfatal], [], [:])
 	MV_ADDFLAGS([my_cxxadd], [CXXFLAGS], [AC_COMPILE_IFELSE], [ \
 			-Wcast-align=strict \
@@ -1032,6 +1030,89 @@ AS_IF([$wsuggest_final_methods],
 		[1],
 		[Define if GCC diagnostic -Wsuggest-final-methods can be used])])
 
+# Check if _Pragma("GCC diagnostic \"-Wzero-as-null-pointer-constant\"") can be used
+AC_MSG_CHECKING([whether pragma GCC diagnostic -Wzero-as-null-pointer-constant can be used])
+MV_RUN_IFELSE_LINK([AC_LANG_PROGRAM([[
+#define GCC_DIAG_STR(s) #s
+#define GCC_DIAG_JOINSTR(x, y) GCC_DIAG_STR(x ## y)
+#define GCC_DIAG_DO_PRAGMA(x) _Pragma (#x)
+#define GCC_DIAG_PRAGMA(x) GCC_DIAG_DO_PRAGMA(GCC diagnostic x)
+#define GCC_DIAG_OFF(x) GCC_DIAG_PRAGMA(push) \
+	GCC_DIAG_PRAGMA(ignored GCC_DIAG_JOINSTR(-W, x))
+#define GCC_DIAG_ON(x) GCC_DIAG_PRAGMA(pop)
+static const char *f(const char *a) {
+	return a;
+}
+		]], [[
+GCC_DIAG_OFF(zero-as-null-pointer-constant)
+	return (f(0) == 0) ? 0 : 1;
+GCC_DIAG_ON(zero-as-null-pointer-constant)
+		]])],
+		[MV_MSG_RESULT([yes])
+		AS_VAR_SET([wzero_as_null_pointer_constant], [:])],
+		[MV_MSG_RESULT([no])
+		AS_VAR_SET([wzero_as_null_pointer_constant], [false])])
+AS_IF([$wzero_as_null_pointer_constant],
+	[AC_DEFINE([WZERO_AS_NULL_POINTER_CONSTANT],
+		[1],
+		[Define if GCC diagnostic -Wzero-as-null-pointer-constant can be used])])
+
+# Check if _Pragma("GCC diagnostic \"-Wsuggest-attribute=const\"") can be used
+AC_MSG_CHECKING([whether pragma GCC diagnostic -Wsuggest-attribute=const can be used])
+MV_RUN_IFELSE_LINK([AC_LANG_PROGRAM([[
+#define GCC_DIAG_STR(s) #s
+#define GCC_DIAG_JOINSTR(x, y) GCC_DIAG_STR(x ## y)
+#define GCC_DIAG_DO_PRAGMA(x) _Pragma (#x)
+#define GCC_DIAG_PRAGMA(x) GCC_DIAG_DO_PRAGMA(GCC diagnostic x)
+#define GCC_DIAG_OFF(x) GCC_DIAG_PRAGMA(push) \
+	GCC_DIAG_PRAGMA(ignored GCC_DIAG_JOINSTR(-W, x))
+#define GCC_DIAG_ON(x) GCC_DIAG_PRAGMA(pop)
+GCC_DIAG_OFF(suggest-attribute=const)
+int f();
+int f() {
+	return 0;
+}
+GCC_DIAG_ON(suggest-attribute=const)
+		]], [[
+	return f();
+		]])],
+		[MV_MSG_RESULT([yes])
+		AS_VAR_SET([wsuggest_attribute_const], [:])],
+		[MV_MSG_RESULT([no])
+		AS_VAR_SET([wsuggest_attribute_const], [false])])
+AS_IF([$wsuggest_attribute_const],
+	[AC_DEFINE([WSUGGEST_ATTRIBUTE_CONST],
+		[1],
+		[Define if GCC diagnostic -Wsuggest-attribute=const can be used])])
+
+# Check if _Pragma("GCC diagnostic \"-Wsuggest-attribute=pure\"") can be used
+AC_MSG_CHECKING([whether pragma GCC diagnostic -Wsuggest-attribute=pure can be used])
+MV_RUN_IFELSE_LINK([AC_LANG_PROGRAM([[
+#define GCC_DIAG_STR(s) #s
+#define GCC_DIAG_JOINSTR(x, y) GCC_DIAG_STR(x ## y)
+#define GCC_DIAG_DO_PRAGMA(x) _Pragma (#x)
+#define GCC_DIAG_PRAGMA(x) GCC_DIAG_DO_PRAGMA(GCC diagnostic x)
+#define GCC_DIAG_OFF(x) GCC_DIAG_PRAGMA(push) \
+	GCC_DIAG_PRAGMA(ignored GCC_DIAG_JOINSTR(-W, x))
+#define GCC_DIAG_ON(x) GCC_DIAG_PRAGMA(pop)
+GCC_DIAG_OFF(suggest-attribute=pure)
+int f();
+int f() {
+	return 0;
+}
+GCC_DIAG_ON(suggest-attribute=pure)
+		]], [[
+	return f();
+		]])],
+		[MV_MSG_RESULT([yes])
+		AS_VAR_SET([wsuggest_attribute_pure], [:])],
+		[MV_MSG_RESULT([no])
+		AS_VAR_SET([wsuggest_attribute_pure], [false])])
+AS_IF([$wsuggest_attribute_pure],
+	[AC_DEFINE([WSUGGEST_ATTRIBUTE_PURE],
+		[1],
+		[Define if GCC diagnostic -Wsuggest-attribute=pure can be used])])
+
 # Check if _Pragma("GCC diagnostic \"-Wgnu-statement-expression\"") can be used in macro
 AC_MSG_CHECKING([whether pragma GCC diagnostic -Wgnu-statement-expression can be used in macro])
 MV_RUN_IFELSE_LINK([AC_LANG_PROGRAM([[

contrib/make.sh

@@ -97,8 +97,7 @@ SetCcache() {
 	ccache -C
 }
 
-clang_cxx=`PATH=${PATH-}${PATH:+:}/usr/lib/llvm/*/bin command -v clang++ 2>/dev/null` \
-  && [ -n "${clang_cxx:++}" ] && clang=: || clang=false
+command -v clang++ >/dev/null 2>&1 && clang=: || clang=false
 
 meson=false
 remove_builddir=false
@@ -274,7 +273,7 @@ then	unset CFLAGS CXXFLAGS LDFLAGS CPPFLAGS CXX
 	CXX=`portageq envvar CXX`
 	export CFLAGS CXXFLAGS LDFLAGS CPPFLAGS
 	if $clang
-	then	CXX=$clang_cxx
+	then	CXX=clang++
 		FilterClang
 	fi
 	[ -z "$CXX" ] || export CXX

meson.build

@@ -385,7 +385,6 @@ if warnings
 	cxxflags_opt += [
 		[ '-fno-common' ],
 		[ '-funsigned-char' ],
-		[ '-fdirectives-only' ],
 		[ '-ftracer' ],
 		[ '-fconcepts' ],
 		[ '-Wpedantic' ],
@@ -400,7 +399,7 @@ if warnings
 		[ '-Wmissing-include-dirs' ],
 		[ '-Wswitch-default' ],
 		[ '-Wstrict-aliasing=1' ],
-		[ '-Wstrict-overflow=5' ],
+		[ '-Wstrict-overflow' ],
 		[ '-Wfloat-equal' ],
 		[ '-Wundef' ],
 		[ '-Wshadow' ],
@@ -459,7 +458,6 @@ if warnings
 		[ '-Wduplicated-branches' ],
 		[ '-Wduplicated-cond' ],
 		[ '-Wstringop-truncation' ],
-		[ '-Wno-c++1z-extensions' ],
 		# [ '-Weverything' ],
 		# [ '-Wno-unknown-warning-option' ],
 		# [ '-fmem-report' ],
@@ -915,6 +913,73 @@ message('Wsuggest-final-methods: ' + wsuggest_final_methods.to_string())
 conf.set('WSUGGEST_FINAL_METHODS', wsuggest_final_methods,
 	description : 'Define if GCC diagnostic -Wsuggest-final-methods can be used')
 
+wzero_as_null_pointer_constant = cxx.links('''
+#define GCC_DIAG_STR(s) #s
+#define GCC_DIAG_JOINSTR(x, y) GCC_DIAG_STR(x ## y)
+#define GCC_DIAG_DO_PRAGMA(x) _Pragma (#x)
+#define GCC_DIAG_PRAGMA(x) GCC_DIAG_DO_PRAGMA(GCC diagnostic x)
+#define GCC_DIAG_OFF(x) GCC_DIAG_PRAGMA(push) \
+	GCC_DIAG_PRAGMA(ignored GCC_DIAG_JOINSTR(-W, x))
+#define GCC_DIAG_ON(x) GCC_DIAG_PRAGMA(pop)
+static const char *f(const char *a) {
+	return a;
+}
+int main() {
+GCC_DIAG_OFF(zero-as-null-pointer-constant)
+	return (f(0) == 0) ? 0 : 1;
+GCC_DIAG_ON(zero-as-null-pointer-constant)
+}
+''', args : flags_fatal)
+message('Wzero-as-null-pointer-constant: ' + wzero_as_null_pointer_constant.to_string())
+conf.set('WZERO_AS_NULL_POINTER_CONSTANT', wzero_as_null_pointer_constant,
+	description : 'Define if GCC diagnostic -Wzero-as-null-pointer-constant can be used')
+
+wsuggest_attribute_const = cxx.links('''
+#define GCC_DIAG_STR(s) #s
+#define GCC_DIAG_JOINSTR(x, y) GCC_DIAG_STR(x ## y)
+#define GCC_DIAG_DO_PRAGMA(x) _Pragma (#x)
+#define GCC_DIAG_PRAGMA(x) GCC_DIAG_DO_PRAGMA(GCC diagnostic x)
+#define GCC_DIAG_OFF(x) GCC_DIAG_PRAGMA(push) \
+	GCC_DIAG_PRAGMA(ignored GCC_DIAG_JOINSTR(-W, x))
+#define GCC_DIAG_ON(x) GCC_DIAG_PRAGMA(pop)
+GCC_DIAG_OFF(suggest-attribute=const)
+int f();
+int f() {
+	return 0;
+}
+int main() {
+GCC_DIAG_OFF(suggest-attribute=const)
+	return f();
+GCC_DIAG_ON(suggest-attribute=const)
+}
+''', args : flags_fatal)
+message('Wsuggest-attribute=const: ' + wzero_as_null_pointer_constant.to_string())
+conf.set('WSUGGEST_ATTRIBUTE_CONST', wsuggest_attribute_const,
+	description : 'Define if GCC diagnostic -Wsuggest-attribute=const can be used')
+
+wsuggest_attribute_pure = cxx.links('''
+#define GCC_DIAG_STR(s) #s
+#define GCC_DIAG_JOINSTR(x, y) GCC_DIAG_STR(x ## y)
+#define GCC_DIAG_DO_PRAGMA(x) _Pragma (#x)
+#define GCC_DIAG_PRAGMA(x) GCC_DIAG_DO_PRAGMA(GCC diagnostic x)
+#define GCC_DIAG_OFF(x) GCC_DIAG_PRAGMA(push) \
+	GCC_DIAG_PRAGMA(ignored GCC_DIAG_JOINSTR(-W, x))
+#define GCC_DIAG_ON(x) GCC_DIAG_PRAGMA(pop)
+GCC_DIAG_OFF(suggest-attribute=pure)
+int f();
+int f() {
+	return 0;
+}
+int main() {
+GCC_DIAG_OFF(suggest-attribute=pure)
+	return f();
+GCC_DIAG_ON(suggest-attribute=pure)
+}
+''', args : flags_fatal)
+message('Wsuggest-attribute=pure: ' + wzero_as_null_pointer_constant.to_string())
+conf.set('WSUGGEST_ATTRIBUTE_PURE', wsuggest_attribute_pure,
+	description : 'Define if GCC diagnostic -Wsuggest-attribute=pure can be used')
+
 wgnu_statement_expression = cxx.links('''
 #define GCC_DIAG_STR(s) #s
 #define GCC_DIAG_JOINSTR(x, y) GCC_DIAG_STR(x ## y)

src/database/header.cc

@@ -139,6 +139,8 @@ void DBHeader::get_overlay_vector(set<ExtendedVersion::Overlay> *overlayset, con
 	}
 }
 
+WSUGGEST_ATTRIBUTE_PURE_OFF
+// Attribute pure can cause subtle errors here
 bool DBHeader::isCurrent() const {
 	for(const DBVersion *acc(accept); *acc != 0; ++acc) {
 		if(version == *acc) {
@@ -147,3 +149,4 @@ bool DBHeader::isCurrent() const {
 	}
 	return false;
 }
+WSUGGEST_ATTRIBUTE_PURE_ON

src/eixTk/argsreader.cc

@@ -92,7 +92,7 @@ GCC_DIAG_ON(sign-conversion)
 	foldAndRemove(opt_table);
 }
 
-eix::TinyUnsigned ArgumentReader::numargs(const Option::Type opt_type) {
+eix::TinyUnsigned ArgumentReader::numargs(Option::Type opt_type) {
 	switch(opt_type) {
 		case Option::STRING:
 		case Option::STRING_OPTIONAL:

src/eixTk/argsreader.h

@@ -174,7 +174,7 @@ class ArgumentReader : public std::vector<Parameter> {
 		/**
 		@return number of args for opt
 		**/
-		ATTRIBUTE_PURE static eix::TinyUnsigned numargs(Option::Type opt_type);
+		ATTRIBUTE_CONST static eix::TinyUnsigned numargs(Option::Type opt_type);
 
 		/**
 		Fold parameter-list so that a option with an arguments has its argument set

src/eixTk/diagnostics.h

@@ -37,9 +37,33 @@
 #define WSUGGEST_FINAL_METHODS_ON
 #endif
 
+#ifdef WZERO_AS_NULL_POINTER_CONSTANT
+#define WZERO_AS_NULL_POINTER_CONSTANT_OFF GCC_DIAG_OFF(zero-as-null-pointer-constant)
+#define WZERO_AS_NULL_POINTER_CONSTANT_ON GCC_DIAG_ON(zero-as-null-pointer-constant)
+#else
+#define WZERO_AS_NULL_POINTER_CONSTANT_OFF
+#define WZERO_AS_NULL_POINTER_CONSTANT_ON
+#endif
+
+#ifdef WSUGGEST_ATTRIBUTE_CONST
+#define WSUGGEST_ATTRIBUTE_CONST_OFF GCC_DIAG_OFF(suggest-attribute=const)
+#define WSUGGEST_ATTRIBUTE_CONST_ON GCC_DIAG_ON(suggest-attribute=const)
+#else
+#define WSUGGEST_ATTRIBUTE_CONST_OFF
+#define WSUGGEST_ATTRIBUTE_CONST_ON
+#endif
+
+#ifdef WSUGGEST_ATTRIBUTE_PURE
+#define WSUGGEST_ATTRIBUTE_PURE_OFF GCC_DIAG_OFF(suggest-attribute=pure)
+#define WSUGGEST_ATTRIBUTE_PURE_ON GCC_DIAG_ON(suggest-attribute=pure)
+#else
+#define WSUGGEST_ATTRIBUTE_PURE_OFF
+#define WSUGGEST_ATTRIBUTE_PURE_ON
+#endif
+
 #ifdef WGNU_STATEMENT_EXPRESSION
 #define WGNU_STATEMENT_EXPRESSION_OFF GCC_DIAG_OFF(gnu-statement-expression)
-#define WGNU_STATEMENT_EXPRESSION_ON GCC_DIAG_OFF(gnu-statement-expression)
+#define WGNU_STATEMENT_EXPRESSION_ON GCC_DIAG_ON(gnu-statement-expression)
 #else
 #define WGNU_STATEMENT_EXPRESSION_OFF
 #define WGNU_STATEMENT_EXPRESSION_ON

src/eixTk/stringlist.h

@@ -23,6 +23,7 @@
 #include "eixTk/dialect.h"
 #endif
 #endif
+#include "eixTk/diagnostics.h"
 #include "eixTk/null.h"
 #include "eixTk/stringtypes.h"
 
@@ -76,19 +77,27 @@ class StringListContent {
 };
 
 inline static bool operator<(const StringListContent& a, const StringListContent& b) {
+WZERO_AS_NULL_POINTER_CONSTANT_OFF
 	return (a.m_list < b.m_list);
+WZERO_AS_NULL_POINTER_CONSTANT_ON
 }
 
 inline static bool operator>(const StringListContent& a, const StringListContent& b) {
+WZERO_AS_NULL_POINTER_CONSTANT_OFF
 	return (a.m_list > b.m_list);
+WZERO_AS_NULL_POINTER_CONSTANT_ON
 }
 
 inline static bool operator<=(const StringListContent& a, const StringListContent& b) {
+WZERO_AS_NULL_POINTER_CONSTANT_OFF
 	return (a.m_list <= b.m_list);
+WZERO_AS_NULL_POINTER_CONSTANT_ON
 }
 
 inline static bool operator>=(const StringListContent& a, const StringListContent& b) {
+WZERO_AS_NULL_POINTER_CONSTANT_OFF
 	return (a.m_list >= b.m_list);
+WZERO_AS_NULL_POINTER_CONSTANT_ON
 }
 
 inline static bool operator==(const StringListContent& a, const StringListContent& b) {

src/output/eix-proto.cc

@@ -9,7 +9,15 @@
 
 #ifdef WITH_PROTOBUF
 #include "eixTk/diagnostics.h"
+WSUGGEST_ATTRIBUTE_PURE_OFF
+WSUGGEST_ATTRIBUTE_CONST_OFF
+WSUGGEST_FINAL_METHODS_OFF
 GCC_DIAG_OFF(sign-conversion)
+
 #include "output/eix.pb.cc"  // NOLINT(build/include)
+
 GCC_DIAG_ON(sign-conversion)
+WSUGGEST_FINAL_METHODS_ON
+WSUGGEST_ATTRIBUTE_CONST_ON
+WSUGGEST_ATTRIBUTE_PURE_ON
 #endif

src/output/print-proto.cc

@@ -24,11 +24,14 @@
 #endif
 
 #ifdef WITH_PROTOBUF
+#include "eixTk/dialect.h"
 #include "eixTk/likely.h"
 #include "eixTk/null.h"
 #include "eixTk/stringtypes.h"
 #include "eixTk/unordered_set.h"
+WSUGGEST_FINAL_METHODS_OFF
 #include "output/eix.pb.h"
+WSUGGEST_FINAL_METHODS_ON
 #include "output/formatstring.h"
 #include "portage/basicversion.h"
 #include "portage/depend.h"