https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79829
Bug ID: 79829
Summary: Assumes host CC and CXX behave the same
Product: gcc
Version: 7.0.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: bootstrap
Assignee: unassigned at gcc dot gnu.org
Reporter: rguenth at gcc dot gnu.org
Target Milestone: ---
When (due to a glitch) having host gcc 4.8 but host g++ 4.3 I run into
[ 121s] g++ -std=gnu++98 -I../../../libcpp -I. -I../../../libcpp/../include
-I
../../../libcpp/include -fmessage-length=0 -O2 -D_FORTIFY_SOURCE=2
-funwind-tab
les -fasynchronous-unwind-tables -g -U_FORTIFY_SOURCE -W -Wall -Wno-narrowing
-W
write-strings -Wmissing-format-attribute -pedantic -Wno-long-long
-fno-exceptio
ns -fno-rtti -I../../../libcpp -I. -I../../../libcpp/../include
-I../../../libcp
p/include -DPACKAGE_SUFFIX=\"-7\" -c -o charset.o -MT charset.o -MMD -MP -MF
.
deps/charset.Tpo ../../../libcpp/charset.c
[ 121s] cc1plus: error: unrecognized command line option "-Wno-narrowing"
because libcpp uses the host _C_ compiler for its ACX_PROG_CC_WARNING_OPTS
checks while later using the host _C++_ compiler for doing the actual
compilation.
It looks like it is ACX_PROG_CC_WARNING_OPTS itself which forces the use of C
here.
Not sure if worth fixing.
