cad/alliance: Unbreak build with GCC 10 (-fno-common default)

/usr/local/bin/ld: /wrkdirs/usr/ports/cad/alliance/work/alliance/src/pat/src/.libs/libPat.a(pat_desc_y.o):(.bss+0x24): multiple definition of `pat_decl_y_errflag'; /wrkdirs/usr/ports/cad/alliance/work/alliance/src/pat/src/.libs/libPat.a(pat_decl_y.o):(.bss+0x20): first defined here
/usr/local/bin/ld: /wrkdirs/usr/ports/cad/alliance/work/alliance/src/pat/src/.libs/libPat.a(pat_desc_y.o):(.bss+0x10): multiple definition of `pat_decl_y_val'; /wrkdirs/usr/ports/cad/alliance/work/alliance/src/pat/src/.libs/libPat.a(pat_decl_y.o):(.bss+0x10): first defined here
/usr/local/bin/ld: /wrkdirs/usr/ports/cad/alliance/work/alliance/src/pat/src/.libs/libPat.a(pat_desc_y.o):(.bss+0x0): multiple definition of `pat_decl_y_lval'; /wrkdirs/usr/ports/cad/alliance/work/alliance/src/pat/src/.libs/libPat.a(pat_decl_y.o):(.bss+0x0): first defined here
/usr/local/bin/ld: /wrkdirs/usr/ports/cad/alliance/work/alliance/src/pat/src/.libs/libPat.a(pat_desc_y.o):(.bss+0x2c): multiple definition of `pat_decl_y_debug'; /wrkdirs/usr/ports/cad/alliance/work/alliance/src/pat/src/.libs/libPat.a(pat_decl_y.o):(.bss+0x24): first defined here

http://package18.nyi.freebsd.org/data/121amd64-default-PR244494/2020-06-10_18h04m44s/logs/errors/alliance-5.1.1_1.log

Also USES=compiler:c++0x & USE_GCC=any can be reduced to USE_GCC=yes

PR:		246700

2 files changed, 24 insertions, 3 deletions

diff --git a/cad/alliance/Makefile b/cad/alliance/Makefile
index fb5466edc10d..67d5001890a9 100644
--- a/cad/alliance/Makefile
+++ b/cad/alliance/Makefile
@@ -22,9 +22,8 @@ BROKEN_aarch64=		fails to link: collect2: error: ld returned 1 exit status
 BUILD_DEPENDS=	convert:graphics/ImageMagick7 \
 		fig2dev:print/transfig
 
-USES=		autoreconf:build compiler:c++0x gmake libtool motif \
-		tar:bz2 xorg
-USE_GCC=	any
+USES=		autoreconf:build gmake libtool motif tar:bz2 xorg
+USE_GCC=	yes
 USE_TEX=	dvipsk:build latex:build
 USE_XORG=	ice sm x11 xext xt
 
@@ -35,6 +34,7 @@ CONFIGURE_ARGS+=--mandir=${MANPREFIX}/man \
 
 MAKE_JOBS_UNSAFE=	yes
 INSTALL_TARGET=	install-strip
+CFLAGS+=	-fcommon
 
 CONFLICTS_INSTALL=	fspclient-*
 
diff --git a/cad/alliance/files/patch-nero_src_MDRGrid.cpp b/cad/alliance/files/patch-nero_src_MDRGrid.cpp
new file mode 100644
index 000000000000..80868b12e0d2
--- /dev/null
+++ b/cad/alliance/files/patch-nero_src_MDRGrid.cpp
@@ -0,0 +1,21 @@
+/usr/local/bin/ld: ./libU.a(MPri.o): in function `CMatrixPri::findfree(int, CNet&)':
+src/nero/src/MPri.cpp:78: undefined reference to `TMatrix<char>::operator[](int)'
+/usr/local/bin/ld: src/nero/src/MPri.cpp:79: undefined reference to `TMatrix<char>::operator[](int)'
+/usr/local/bin/ld: ./libU.a(MPri.o): in function `CMatrixPri::take(int, int)':
+src/nero/src/MPri.cpp:284: undefined reference to `TMatrix<char>::operator[](int)'
+/usr/local/bin/ld: ./libU.a(MPri.o): in function `operator<<(std::ostream&, CMatrixPri&)':
+src/nero/src/MPri.cpp:317: undefined reference to `TMatrix<char>::operator[](int)'
+/usr/local/bin/ld: ./libU.a(MPri.o): in function `CMatrixPri::load(CNet&, bool, int)':
+src/nero/src/MPri.cpp:175: undefined reference to `TMatrix<char>::operator[](int)'
+/usr/local/bin/ld: ./libU.a(MPri.o):src/nero/src/MPri.cpp:186: more undefined references to `TMatrix<char>::operator[](int)' follow
+
+--- nero/src/MDRGrid.cpp.orig	2014-08-02 23:38:00 UTC
++++ nero/src/MDRGrid.cpp
+@@ -17,6 +17,7 @@
+ 
+ 
+ # include  "MDefs.h"
++template class TMatrix<char>;
+ 
+ 
+