Hi!
Ludovic Courtès <l...@gnu.org> skribis:
> /tmp/guix-build-gcc-10.1.0.drv-0/build/prev-x86_64-unknown-linux-gnu/libstdc++-v3/config.log
> reads this:
>
> configure:19924: checking for float trig functions
> configure:19948: /tmp/guix-build-gcc-10.1.0.drv-0/build/./gcc/xgcc
> -shared-libgcc -B/tmp/guix-build-gcc-10.1.0.drv-0/build/./gcc -nostdinc++
> -L/tmp/guix-build-gcc-10.1.0.drv-0/build/x86_64-unknown-linux-gnu/libstdc++-v3/src
>
> -L/tmp/guix-build-gcc-10.1.0.drv-0/build/x86_64-unknown-linux-gnu/libstdc++-v3/src/.libs
>
> -L/tmp/guix-build-gcc-10.1.0.drv-0/build/x86_64-unknown-linux-gnu/libstdc++-v3/libsupc++/.libs
>
> -B/gnu/store/jrzxs91zhpf6yr5fxisn3jjj7xai8zlk-gcc-10.1.0/x86_64-unknown-linux-gnu/bin/
>
> -B/gnu/store/jrzxs91zhpf6yr5fxisn3jjj7xai8zlk-gcc-10.1.0/x86_64-unknown-linux-gnu/lib/
> -isystem
> /gnu/store/jrzxs91zhpf6yr5fxisn3jjj7xai8zlk-gcc-10.1.0/x86_64-unknown-linux-gnu/include
> -isystem
> /gnu/store/jrzxs91zhpf6yr5fxisn3jjj7xai8zlk-gcc-10.1.0/x86_64-unknown-linux-gnu/sys-include
> -fno-checking -c -fno-builtin -D_GNU_SOURCE conftest.cpp >&5
> In file included from
> /gnu/store/rn75fm7adgx3pw5j8pg3bczfqq1y17lk-gcc-7.5.0/include/c++/math.h:36,
> from conftest.cpp:122:
> /gnu/store/rn75fm7adgx3pw5j8pg3bczfqq1y17lk-gcc-7.5.0/include/c++/cmath:41:10:
> fatal error: bits/c++config.h: No such file or directory
> 41 | #include <bits/c++config.h>
> | ^~~~~~~~~~~~~~~~~~
> compilation terminated.
> configure:19948: $? = 1
> configure: failed program was:
>
> [...]
>
> | /* end confdefs.h. */
> | #include <math.h>
> | int
> | main ()
> | {
> | acosf (0); asinf (0); atanf (0); cosf (0); sinf (0); tanf (0); coshf (0);
> sinhf (0); tanhf (0);
> | ;
> | return 0;
> | }
> configure:19962: result: no
The attached patch addresses this with a questionable yet efficient
hack. The test cases reported by Maxim and by Erik Garrison now build
fine.
I’ve asked for guidance for a proper fix at
<https://gcc.gnu.org/pipermail/gcc-help/2020-July/139204.html>, but in
the meantime, I’m happy to go with this patch.
Thoughts?
Thanks,
Ludo’.
diff --git a/gnu/packages/gcc.scm b/gnu/packages/gcc.scm
index 9ff5e3d7c0..8969fefd84 100644
--- a/gnu/packages/gcc.scm
+++ b/gnu/packages/gcc.scm
@@ -530,6 +530,12 @@ Go. It also includes runtime support libraries for these languages.")
(patches (search-patches "gcc-strmov-store-file-names.patch"
"gcc-7-libsanitizer-mode-size.patch"
"gcc-5.0-libvtv-runpath.patch"))))
+ (inputs
+ ;; XXX: This gross hack allows us to have libstdc++'s <bits/c++config.h>
+ ;; in the search path, thereby avoiding misconfiguration of libstdc++:
+ ;; <https://bugs.gnu.org/42392>.
+ `(("libstdc++" ,libstdc++-headers)
+ ,@(package-inputs gcc-6)))
(description
"GCC is the GNU Compiler Collection. It provides compiler front-ends
for several languages, including C, C++, Objective-C, Fortran, Ada, and Go.
@@ -607,6 +613,31 @@ using compilers other than GCC."
(propagated-inputs '())
(synopsis "GNU C++ standard library")))
+(define libstdc++
+ ;; Libstdc++ matching the default GCC.
+ (make-libstdc++ gcc))
+
+(define libstdc++-headers
+ ;; XXX: This package is for internal use to work around
+ ;; <https://bugs.gnu.org/42392> (see above). The main difference compared
+ ;; to the libstdc++ headers that come with 'gcc' is that <bits/c++config.h>
+ ;; is right under include/c++ and not under
+ ;; include/c++/x86_64-unknown-linux-gnu (aka. GPLUSPLUS_TOOL_INCLUDE_DIR).
+ (package
+ (inherit libstdc++)
+ (name "libstdc++-headers")
+ (outputs '("out"))
+ (build-system trivial-build-system)
+ (arguments
+ '(#:builder (let* ((out (assoc-ref %outputs "out"))
+ (libstdc++ (assoc-ref %build-inputs "libstdc++")))
+ (mkdir out)
+ (mkdir (string-append out "/include"))
+ (symlink (string-append libstdc++ "/include")
+ (string-append out "/include/c++")))))
+ (inputs `(("libstdc++" ,libstdc++)))
+ (synopsis "Headers of GNU libstdc++")))
+
(define-public libstdc++-4.9
(make-libstdc++ gcc-4.9))
