I've tried building bash on AIX 6.1 with gcc, and it failed in examples/loadables with an "unknow option" error.

The workaround turned out to be this change:

diff --git a/examples/loadables/Makefile.in b/examples/loadables/Makefile.in
index be46121b..b275e2fb 100644
--- a/examples/loadables/Makefile.in
+++ b/examples/loadables/Makefile.in
@@ -87,7 +87,7 @@ CCFLAGS = $(DEFS) $(LOCAL_DEFS) $(LOCAL_CFLAGS) $(CPPFLAGS) $(CFLAGS)
 SHOBJ_CC = @SHOBJ_CC@
 SHOBJ_CFLAGS = @SHOBJ_CFLAGS@
 SHOBJ_LD = @SHOBJ_LD@
-SHOBJ_LDFLAGS = @SHOBJ_LDFLAGS@ @LDFLAGS@
+SHOBJ_LDFLAGS = @SHOBJ_LDFLAGS@
 SHOBJ_XLDFLAGS = @SHOBJ_XLDFLAGS@
 SHOBJ_LIBS = @SHOBJ_LIBS@
 SHOBJ_STATUS = @SHOBJ_STATUS@

The reason for this is that in support/shobj-conf SHOBJ_LD is set to 'ld', but LDFLAGS contains gcc-specific flags for linking (which can be passed to the linker using '-Wl,-linkerflag'). When this is directly given to the AIX linker, it's not recognized by it. In SHOBJ_LDFLAGS there are bare linker flags so that's not a problem.

I see 2 possible solutions:
1. Remove LDFLAGS from the invocation as I did - don't know if other platforms need it, on Linux I could build without it
2. Change support/shobj-conf so that for aix*-gcc it is ${CC} which is invoked as SHOBJ_LD, and the linker flags are prefixed with '-Wl,'.