This is an auto-filled bug because media-libs/libmng calls cc directly.
The issue was originally discovered on arm64, but it may be reproducible on other arches as well.
If you think that a different summary clarifies the issue better, feel free to change it.
Attached build log and emerge --info.
If you think it doesn't make sense fix these type of issues, I'd like to point out that won't be possible use a different CC implementation (like clang) by setting the CC variable. So this issue has been reproduced by setting the CC variable to aarch64-unknown-linux-gnu-gcc and by removing the /usr/bin/cc - /usr/bin/gcc binaries.
Created attachment 635904 [details]
build log and emerge --info
The bug has been closed via the following commit(s):
Author: Sergei Trofimovich <firstname.lastname@example.org>
AuthorDate: 2020-05-25 08:37:05 +0000
Commit: Sergei Trofimovich <email@example.com>
CommitDate: 2020-05-25 08:37:27 +0000
media-libs/libmng: don't call 'gcc' in src_prepare(), bug #720884
Before the change src_prepare() was calling 'emake distclean'.
That forced reconfiguration with default CC=gcc.
The change just deletes files which 'make distclean' would delete.
Reported-by: Agostino Sarubbo
Package-Manager: Portage-2.3.100, Repoman-2.3.22
Signed-off-by: Sergei Trofimovich <firstname.lastname@example.org>
media-libs/libmng/libmng-2.0.3.ebuild | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)