Bug: GCC riscv building fails at self-tests with specific march

Bug: GCC riscv building fails at self-tests with specific march

[Michael T. Kloos]

I encountered a bug when trying to build a RISC-V GCC cross-compiler.  I
believe that the most relevant configure options that I used are:
--disable-multilib --with-arch=rv32ia --with-abi=ilp32 However, I can
post a full list if needed.  I have the GCC git tree located at the path
"/home/quantum/devel/git/gcc" and am building it inside the
sub-directory "build1".  It seems to fail when attempting to build the
self-tests.  Here is an excerpt from the build output:
/home/quantum/devel/git/gcc/build1/./gcc/xgcc
-B/home/quantum/devel/git/gcc/build1/./gcc/  -xc -nostdinc /dev/null -S
-o /dev/null -fself-test=.././../gcc/testsuite/selftests
/home/quantum/devel/git/gcc/build1/./gcc/xgcc
-B/home/quantum/devel/git/gcc/build1/./gcc/  -xc++ -nostdinc /dev/null
-S -o /dev/null -fself-test=.././../gcc/testsuite/selftests cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension cc1plus: error:
'-mdiv' requires '-march' to subsume the 'M' extension It seems to be
trying to build test suites that are in conflict with my march settings.
Interestingly, I didn't have this issue when trying to build the release
version tagged "releases/gcc-13.2.0".  However, I wanted to use some
newer features that were only merged less than a month ago.  I tried to
build the GIT tree and encountered this error.  I attempted to bisect
the issue and found that it only happens when gcc/DEV-PHASE is set to:
experimental I'm not very familar with GCC's build system, but this
suggests to me that the tests are only conditionally built on
experimental/development codebase snapshots.  Michael T. Kloos

Re: Bug: GCC riscv building fails at self-tests with specific march

[Michael T. Kloos]

Sorry for the formatting break.  Resending...

I encountered a bug when trying to build a RISC-V GCC cross-compiler.  I 
believe that the most relevant configure options that I used are: 

	--disable-multilib --with-arch=rv32ia --with-abi=ilp32

However, I can post a full list if needed.  

I have the GCC git tree located at the path "/home/quantum/devel/git/gcc" 
and am building it inside the sub-directory "build1".  It seems to fail 
when attempting to build the self-tests.  Here is an excerpt from the 
build output: 

/home/quantum/devel/git/gcc/build1/./gcc/xgcc
-B/home/quantum/devel/git/gcc/build1/./gcc/  -xc -nostdinc /dev/null -S -o /dev/null -fself-test=.././../gcc/testsuite/selftests
/home/quantum/devel/git/gcc/build1/./gcc/xgcc
-B/home/quantum/devel/git/gcc/build1/./gcc/  -xc++ -nostdinc /dev/null -S -o /dev/null -fself-test=.././../gcc/testsuite/selftests
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 
	cc1plus: error: '-mdiv' requires '-march' to subsume the 'M' extension 

It seems to be trying to build test suites that are in conflict with my 
march settings.  

Interestingly, I didn't have this issue when trying to build the release 
version tagged "releases/gcc-13.2.0".  However, I wanted to use some 
newer features that were only merged less than a month ago.  I tried to 
build the GIT tree and encountered this error.  I attempted to bisect 
the issue and found that it only happens when "gcc/DEV-PHASE" is set to: 

	experimental

I'm not very familar with GCC's build system, but this suggests to me 
that the tests are only conditionally built on experimental/development 
codebase snapshots.  

	Michael T. Kloos