Link error on x86_64-pc-cygwin

[fd00]

Link error on x86_64-pc-cygwin occurs.

Is configure option wrong?
Or gcc's bug?

$ cat hello.rs
fn main() {
    println!("Hello, world!");
}

$ TMPDIR=/tmp /tmp/gcc-rust/usr/local/bin/gccrs.exe -v hello.rs
Using built-in specs.
COLLECT_GCC=/tmp/gcc-rust/usr/local/bin/gccrs
COLLECT_LTO_WRAPPER=/tmp/gcc-rust/usr/local/bin/../libexec/gcc/x86_64-pc-cygwin/10.0.0/lto-wrapper.exe
Target: x86_64-pc-cygwin
Configured with: ./configure --disable-bootstrap --enable-multilib --enable-languages=c,c++,rust
Thread model: single
Supported LTO compression algorithms: zlib zstd
gcc version 10.0.0 20191127 (experimental) (GCC)
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
 /tmp/gcc-rust/usr/local/bin/../libexec/gcc/x86_64-pc-cygwin/10.0.0/rust1.exe hello.rs -quiet -dumpbase hello.rs -mtune=generic -march=x86-64 -auxbase hello -version -L/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0 -L/tmp/gcc-rust/usr/local/bin/../lib/gcc -L/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/../../../../lib -L/lib/../lib -L/usr/lib/../lib -L/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/../../.. -o /tmp/ccr9IdMy.s
GNU Rust (GCC) version 10.0.0 20191127 (experimental) (x86_64-pc-cygwin)
        compiled by GNU C version 9.3.0, GMP version 6.2.0, MPFR version 4.0.2-p6, MPC version 1.1.0, isl version isl-0.22.1-GMP

GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
GNU Rust (GCC) version 10.0.0 20191127 (experimental) (x86_64-pc-cygwin)
        compiled by GNU C version 9.3.0, GMP version 6.2.0, MPFR version 4.0.2-p6, MPC version 1.1.0, isl version isl-0.22.1-GMP

GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Preparing to parse files.
about to parse expr (in expr without block method)
beginning null denotation identifier handling
current peek token when starting path pratt parse: '!'
current token (just about to return path to null denotation): '!'
finished null denotation identifier path parsing - next is branching
new delim token tree parsing begun
ast token created with str 'Hello, world!'
finished parsing new delim token tree - peeked token is now ';' while t is ')'
successfully parsed macro invocation (via partial)
finished parsing null denotation
null denotation is not null - going on to left denotation
initial rbp: '0', initial lbp: '0' (for ';')
successfully parsed expr in parse_expr - returning
successfully parsed expr (in expr without block method)
about to call the impl for clone expr without block
expr to expr without block conversion didn't error
expr to expr without block conversion was successful; returning
SUCCESSFULLY PARSED CRATE
ran register_plugins (with no body)
SUCCESSFULLY REGISTERED PLUGINS
started injection
finished injection
SUCCESSFULLY FINISHED INJECTION
started expansion
finished expansion
SUCCESSFULLY FINISHED EXPANSION
started name resolution
finished name resolution
SUCCESSFULLY FINISHED RESOLUTION
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
 as -o /tmp/ccpwggue.o /tmp/ccr9IdMy.s
COMPILER_PATH=/tmp/gcc-rust/usr/local/bin/../libexec/gcc/x86_64-pc-cygwin/10.0.0/:/tmp/gcc-rust/usr/local/bin/../libexec/gcc/
LIBRARY_PATH=/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/:/tmp/gcc-rust/usr/local/bin/../lib/gcc/:/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/../../../../lib/:/lib/../lib/:/usr/lib/../lib/:/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
 /tmp/gcc-rust/usr/local/bin/../libexec/gcc/x86_64-pc-cygwin/10.0.0/collect2.exe -plugin /tmp/gcc-rust/usr/local/bin/../libexec/gcc/x86_64-pc-cygwin/10.0.0/cyglto_plugin-0.dll -plugin-opt=/tmp/gcc-rust/usr/local/bin/../libexec/gcc/x86_64-pc-cygwin/10.0.0/lto-wrapper.exe -plugin-opt=-fresolution=/tmp/ccHmliAY.res -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lcygwin -plugin-opt=-pass-through=-ladvapi32 -plugin-opt=-pass-through=-lshell32 -plugin-opt=-pass-through=-luser32 -plugin-opt=-pass-through=-lkernel32 -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc -m i386pep --wrap _Znwm --wrap _Znam --wrap _ZdlPv --wrap _ZdaPv --wrap _ZnwmRKSt9nothrow_t --wrap _ZnamRKSt9nothrow_t --wrap _ZdlPvRKSt9nothrow_t --wrap _ZdaPvRKSt9nothrow_t -Bdynamic --dll-search-prefix=cyg --tsaware /lib/../lib/crt0.o /tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/crtbegin.o -L/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0 -L/tmp/gcc-rust/usr/local/bin/../lib/gcc -L/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/../../../../lib -L/lib/../lib -L/usr/lib/../lib -L/tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/../../.. /tmp/ccpwggue.o -lgcc_s -lgcc -lcygwin -ladvapi32 -lshell32 -luser32 -lkernel32 -lgcc_s -lgcc /lib/../lib/default-manifest.o /tmp/gcc-rust/usr/local/bin/../lib/gcc/x86_64-pc-cygwin/10.0.0/crtend.o
/usr/bin/ld: /lib/../lib/libcygwin.a(libcmain.o): in function `main':
/usr/src/debug/cygwin-3.1.4-1/winsup/cygwin/lib/libcmain.c:37: undefined reference to `WinMain'
/usr/src/debug/cygwin-3.1.4-1/winsup/cygwin/lib/libcmain.c:37:(.text.startup+0x7f): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `WinMain'
collect2: error: ld returned 1 exit status

$ TMPDIR=/tmp /tmp/gcc-rust/usr/local/bin/gccrs.exe -c hello.rs
$ objdump -t hello.o | grep __main
$

[philberty]

This is a bug with the compiler were not detecting the main and generating the system specific main method in the compiler yet. There are 2 methods for doing this properly and i havent decided the correct approach yet.

[philberty]

Is it possible to retest this now since #136 has been fixed.

[fd00]

I tried the latest version and got another error.

$ git log | head -1
commit 93b991e60438c7fb939a4cc8df737e6f7a142c07
$ cat hello.rs
fn main() {
    println!("Hello, world!");
}
$ TMPDIR=/tmp /opt/gccrs/bin/gccrs.exe -v hello.rs
Using built-in specs.
COLLECT_GCC=/opt/gccrs/bin/gccrs
COLLECT_LTO_WRAPPER=/opt/gccrs/libexec/gcc/x86_64-pc-cygwin/11.0.0/lto-wrapper.exe
Target: x86_64-pc-cygwin
Configured with: ./configure --prefix=/opt/gccrs --disable-bootstrap --enable-multilib --enable-languages=c,c++,rust
Thread model: single
Supported LTO compression algorithms: zlib zstd
gcc version 11.0.0 20201127 (experimental) (GCC)
COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64' '-dumpdir' 'a-'
 /opt/gccrs/libexec/gcc/x86_64-pc-cygwin/11.0.0/rust1.exe hello.rs -quiet -dumpdir a- -dumpbase hello.rs -dumpbase-ext .rs -mtune=generic -march=x86-64 -version -L/opt/gccrs/lib/gcc/x86_64-pc-cygwin/11.0.0 -L/opt/gccrs/lib/gcc/x86_64-pc-cygwin/11.0.0/../../../../lib -L/lib/../lib -L/usr/lib/../lib -L/opt/gccrs/lib/gcc/x86_64-pc-cygwin/11.0.0/../../.. -o /tmp/ccWBnGUF.s
GNU Rust (GCC) version 11.0.0 20201127 (experimental) (x86_64-pc-cygwin)
        compiled by GNU C version 10.2.0, GMP version 6.2.1, MPFR version 4.1.0, MPC version 1.2.1, isl version isl-0.22.1-GMP

GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
GNU Rust (GCC) version 11.0.0 20201127 (experimental) (x86_64-pc-cygwin)
        compiled by GNU C version 10.2.0, GMP version 6.2.1, MPFR version 4.1.0, MPC version 1.2.1, isl version isl-0.22.1-GMP

GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Preparing to parse files.
Attempting to parse file: hello.rs
beginning null denotation identifier handling
current peek token when starting path pratt parse: '!'
current token (just about to return path to null denotation): '!'
finished null denotation identifier path parsing - next is branching
ast token created with str 'Hello, world!'
finished parsing new delim token tree - peeked token is now ';' while t is ')'
successfully parsed macro invocation (via partial)
SUCCESSFULLY PARSED CRATE
ran register_plugins (with no body)
SUCCESSFULLY REGISTERED PLUGINS
started injection
finished injection
SUCCESSFULLY FINISHED INJECTION
started expansion
finished expansion
SUCCESSFULLY FINISHED EXPANSION
started name resolution
finished name resolution
SUCCESSFULLY FINISHED RESOLUTION
started lowering AST
hello.rs:2:5: fatal error: Failed to lower expr: [MacroInvocation: println!("Hello, world!")]
    2 |     println!("Hello, world!");
      |     ^
compilation terminated.
$