[Bug target/66579] New: frv target: -gsplit-dwarf confuses assembler
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66579 Bug ID: 66579 Summary: frv target: -gsplit-dwarf confuses assembler Product: gcc Version: 5.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: nicstange at gmail dot com Target Milestone: --- Created attachment 35797 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35797&action=edit Testcase Adding `-gsplit-dwarf' leads to doubly defined symbols even in trivial testcases (see attached). # gcc-5.1.0/frv-linux/bin/frv-linux-gcc -c -gsplit-dwarf -o test.o test.c /tmp/cc2kwvh4.s: Assembler messages: /tmp/cc2kwvh4.s:225: Error: symbol `.LSLT0' is already defined /tmp/cc2kwvh4.s:229: Error: symbol `.LASLTP0' is already defined /tmp/cc2kwvh4.s:254: Error: symbol `.LELTP0' is already defined /tmp/cc2kwvh4.s:255: Error: symbol `.LELT0' is already defined # gcc-5.1.0/frv-linux/bin/frv-linux-gcc -v Using built-in specs. COLLECT_GCC=./gcc-5.1.0/frv-linux/bin/frv-linux-gcc COLLECT_LTO_WRAPPER=/mnt/scratch/nic/cc/gcc-5.1.0/frv-linux/libexec/gcc/frv-linux/5.1.0/lto-wrapper Target: frv-linux Configured with: ../gcc-5.1.0/configure --prefix=/mnt/scratch/nic/cc/gcc-5.1.0/frv-linux --target=frv-linux --target=frv-linux --enable-targets=all --enable-languages=c --without-headers --enable-sjlj-exceptions --with-system-libunwind --disable-nls --disable-threads --disable-shared --disable-libmudflap --disable-libssp --disable-libgomp --disable-decimal-float --enable-checking=release --disable-bootstrap --disable-multilib --host=x86_64-linux-gnu --build=x86_64-linux-gnu --with-newlib : (reconfigured) ../gcc-5.1.0/configure --prefix=/mnt/scratch/nic/cc/gcc-5.1.0/frv-linux --target=frv-linux --target=frv-linux --enable-targets=all --enable-languages=c --without-headers --enable-sjlj-exceptions --with-system-libunwind --disable-nls --disable-threads --disable-shared --disable-libmudflap --disable-libssp --disable-libgomp --disable-decimal-float --enable-checking=release --disable-bootstrap --disable-multilib --host=x86_64-linux-gnu --build=x86_64-linux-gnu --with-newlib --disable-libquadmath : (reconfigured) ../gcc-5.1.0/configure --prefix=/mnt/scratch/nic/cc/gcc-5.1.0/frv-linux --target=frv-linux --target=frv-linux --enable-targets=all --enable-languages=c --without-headers --enable-sjlj-exceptions --with-system-libunwind --disable-nls --disable-threads --disable-shared --disable-libmudflap --disable-libssp --disable-libgomp --disable-decimal-float --enable-checking=release --disable-bootstrap --disable-multilib --host=x86_64-linux-gnu --build=x86_64-linux-gnu --with-newlib --disable-libquadmath --disable-libatomic Thread model: single gcc version 5.1.0 (GCC)
[Bug target/66579] frv target: -gsplit-dwarf confuses assembler
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66579 --- Comment #1 from Nicolai Stange --- Created attachment 35798 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35798&action=edit Output of `gcc -S -gsplit-dwarf' on Testcase
[Bug c/66963] New: __builtin_constant_p and __builtin_choose_expr do not agree on what is a constexpr with -O2
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66963
Bug ID: 66963
Summary: __builtin_constant_p and __builtin_choose_expr do not
agree on what is a constexpr with -O2
Product: gcc
Version: 5.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: nicstange at gmail dot com
Target Milestone: ---
The first argument to __builtin_choose_expr() must be a constant expression.
However, at -O2, the following does not work:
int foo (void)
{
const int a = 0;
return __builtin_choose_expr(__builtin_choose_expr(__builtin_constant_p(a +
1), a + 1, 0),
0, 0);
}
test.c: In function ‘foo’:
test.c:4:10: error: first argument to ‘__builtin_choose_expr’ not a constant
return __builtin_choose_expr(__builtin_choose_expr(__builtin_constant_p(a +
1), a + 1, 0),
^
Obviously, __builtin_constant_p() recognizes 'a+1' as being constant-foldable
and returns nonzero. This makes the inner __builtin_choose_expr() select its
second argument, i.e. 'a+1'. The outer __builtin_choose_expr() in turn refuses
to accept that 'a+1' as a constant expression for its condition argument
because it does not recognize it as a constexpr.
As a workaround, you can wrap the 'a+1' in a __builtin_expect() which seems to
apply constant-folding in the same way the __builtin_constant_p() does:
__builtin_choose_expr(__builtin_choose_expr(__builtin_constant_p(a + 1),
__builtin_expect(a + 1, 1), 0),
0, 0);
Thus, it looks like constant folding is not applied to
__builtin_choose_expr()'s first argument.
[Bug c/66963] __builtin_constant_p and __builtin_choose_expr do not agree on what is a constexpr with -O2
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66963 --- Comment #3 from Nicolai Stange --- (In reply to Andrew Pinski from comment #1) > I thought this is documented somewhere but __builtin_choose_expr only really > accept constant literals and not constexprs. https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html explicitly mentions integer constant expressions though. Quote: "This built-in function returns exp1 if const_exp, which is an integer constant expression, is nonzero."
[Bug c/66963] __builtin_constant_p and __builtin_choose_expr do not agree on what is a constexpr with -O2
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66963 --- Comment #4 from Nicolai Stange --- Sorry, misunderstanding at my side. You probably did not mean constexprs in the sense of C99, 6.6, but constexprs in the sense of constant folded expressions.
[Bug c/66963] __builtin_constant_p and __builtin_choose_expr do not agree on what is a constexpr with -O2
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66963 --- Comment #6 from Nicolai Stange --- Thank you for your clarifications, Andrew and Joseph. As far as I am concerned, this bug can be marked as resolved/rejected/whatever you like.
