Bug 653686 – sys-devel/gcc: gcc -Q --help=target --help=optimizers does not list correctly which parameters are activated

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description burak 2018-04-21 10:48:08 UTC]

Hi,

I'm using stable amd64 architecture. sys-devel/gcc-6.4.0-r1 which is stable, hits the gcc bug #39851 related gcc bugzilla page is

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=39851


On my system,

$ diff -u0 <(gcc -Q -march=ivybridge --help=target) <(gcc -march=native -Q --help=target)
--- /dev/fd/63	2018-04-21 13:30:03.531304518 +0300
+++ /dev/fd/62	2018-04-21 13:30:03.532304533 +0300
@@ -16 +16 @@
-  -maes                       		[disabled]
+  -maes                       		[enabled]
@@ -26 +26 @@
-  -mavx                       		[disabled]
+  -mavx                       		[enabled]
@@ -50 +50 @@
-  -mcx16                      		[disabled]
+  -mcx16                      		[enabled]
@@ -53 +53 @@
-  -mf16c                      		[disabled]
+  -mf16c                      		[enabled]
@@ -61 +61 @@
-  -mfsgsbase                  		[disabled]
+  -mfsgsbase                  		[enabled]
@@ -63 +63 @@
-  -mfxsr                      		[disabled]
+  -mfxsr                      		[enabled]
@@ -82 +82 @@
-  -mmmx                       		[disabled]
+  -mmmx                       		[enabled]
@@ -93 +93 @@
-  -mno-sse4                   		[enabled]
+  -mno-sse4                   		[disabled]
@@ -99 +99 @@
-  -mpclmul                    		[disabled]
+  -mpclmul                    		[enabled]
@@ -102 +102 @@
-  -mpopcnt                    		[disabled]
+  -mpopcnt                    		[enabled]
@@ -108 +108 @@
-  -mrdrnd                     		[disabled]
+  -mrdrnd                     		[enabled]
@@ -117 +117 @@
-  -msahf                      		[disabled]
+  -msahf                      		[enabled]
@@ -121,2 +121,2 @@
-  -msse                       		[disabled]
-  -msse2                      		[disabled]
+  -msse                       		[enabled]
+  -msse2                      		[enabled]
@@ -124,4 +124,4 @@
-  -msse3                      		[disabled]
-  -msse4                      		[disabled]
-  -msse4.1                    		[disabled]
-  -msse4.2                    		[disabled]
+  -msse3                      		[enabled]
+  -msse4                      		[enabled]
+  -msse4.1                    		[enabled]
+  -msse4.2                    		[enabled]
@@ -131 +131 @@
-  -mssse3                     		[disabled]
+  -mssse3                     		[enabled]
@@ -141 +141 @@
-  -mtune=                     		
+  -mtune=                     		ivybridge
@@ -148 +148 @@
-  -mxsave                     		[disabled]
+  -mxsave                     		[enabled]
@@ -150 +150 @@
-  -mxsaveopt                  		[disabled]
+  -mxsaveopt                  		[enabled]


gcc svn revision 252797 fixes this issue for gcc-6 branch and rev 25278 fixes for gcc-ada 
svn diff svn://gcc.gnu.org/svn/gcc/branches/gcc-6-branch -r252796:252798  > fix-proper-help-query.patch

I was applied this patch (with excluding ChangeLog because patching was failed), issue is solved.

Also, this patch also fixes -Q -help=optimizers, like
$ diff -u0 old-o2 new-O2 
--- old-o2	2018-04-20 23:42:36.503581755 +0300
+++ new-O2	2018-04-21 02:59:52.745378786 +0300
@@ -7,2 +7,2 @@
-  -falign-functions           		[enabled]
-  -falign-jumps               		[enabled]
+  -falign-functions           		[disabled]
+  -falign-jumps               		[disabled]
@@ -10 +10 @@
-  -falign-loops               		[enabled]
+  -falign-loops               		[disabled]
@@ -96 +96 @@
-  -fomit-frame-pointer        		[disabled]
+  -fomit-frame-pointer        		[enabled]
@@ -110 +110 @@
-  -freg-struct-return         		[disabled]
+  -freg-struct-return         		[enabled]
@@ -211 +211 @@
-  -funwind-tables             		[disabled]
+  -funwind-tables             		[enabled]

Regards

[Comment 1 Sergei Trofimovich (RETIRED) 2018-11-27 23:35:42 UTC]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=39851 was released as part of gcc-6.5.0 (in ~arch now).